1
|
Catalán-Salas V, Sagredo P, Melgarejo W, Donoso MV, Cárdenas JC, Zakarian A, Valdés D, Acuña-Castillo C, Huidobro-Toro JP. 17-β-estradiol and phytoestrogens elicit NO production and vasodilatation through PI3K, PKA and EGF receptors pathways, evidencing functional selectivity. Eur J Pharmacol 2024:176636. [PMID: 38729417 DOI: 10.1016/j.ejphar.2024.176636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 04/24/2024] [Accepted: 05/03/2024] [Indexed: 05/12/2024]
Abstract
Endothelial cells express multiple receptors mediating estrogen responses; including the G protein-coupled estrogen receptor (GPER). Past studies on nitric oxide (NO) production elicited by estrogens raised the question whether 17-β-estradiol (E2) and natural phytoestrogens activate equivalent mechanisms. We hypothesized that E2 and phytoestrogens elicit NO production via coupling to distinct intracellular pathways signalling. To this aim, perfusion of E2 and phytoestrogens to the precontracted rat mesentery bed examined vasorelaxation, while fluorescence microscopy on primary endothelial cells cultures quantified single cell NO production determined following 4-amino-5-methylamino-2',7'-difluoroescein diacetate (DAF) incubation. Daidzein (DAI) and genistein (GEN) induced rapid vasodilatation associated to NO production. Multiple estrogen receptor activity was inferred based on the reduction of DAF-NO signals; G-36 (GPER antagonist) reduced 75 % of all estrogen responses, while fulvestrant (selective nuclear receptor antagonist) reduced significantly more the phytoestrogens responses than E2. The joint application of both antagonists abolished the E2 response but not the phytoestrogen-induced DAF-NO signals. Wortmannin or LY-294002 (PI3K inhibitors), reduced by 90% the E2-evoked signal while altering significantly less the DAI-induced response. In contrast, H-89 (PKA inhibitor), elicited a 23% reduction of the E2-induced signal while blocking 80% of the DAI-induced response. Desmethylxestospongin-B (IP3 receptor antagonist), decreased to equal extent the E2 or the DAI-induced signal. Epidermal growth factor (EGF) induced NO production, cell treatment with AG-1478, an EGF receptor kinase inhibitor reduced 90% DAI-induced response while only 53% the E2-induced signals; highlighting GPER induced EGF receptor trans-modulation. Receptor functional selectivity may explain distinct signalling pathways mediated by E2 and phytoestrogens.
Collapse
Affiliation(s)
- Vicente Catalán-Salas
- Laboratorio de Farmacología, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, 9170022, Chile
| | - Pablo Sagredo
- Laboratorio de Farmacología, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, 9170022, Chile
| | - Williams Melgarejo
- Laboratorio de Farmacología, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, 9170022, Chile
| | - M Verónica Donoso
- Laboratorio de Farmacología, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, 9170022, Chile
| | - J Cesar Cárdenas
- Centro de Biología Integrativa, Facultad de Ciencias, Universidad Mayor, Santiago, 8580745, Chile; Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile; Buck Institute for Research on Aging, Novato, CA 94945, USA; Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA
| | - Daniel Valdés
- Laboratorio de Farmacología, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, 9170022, Chile
| | - Claudio Acuña-Castillo
- Laboratorio de Farmacología, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, 9170022, Chile
| | - J Pablo Huidobro-Toro
- Laboratorio de Farmacología, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, 9170022, Chile; Unidad de Nanoseguridad, Centro de Nanociencia y Nanotecnología, CEDNNA, Santiago, Chile.
| |
Collapse
|
2
|
Smith-Cortinez N, Heegsma J, Podunavac M, Zakarian A, Cardenas JC, Faber KN. Novel Inositol 1,4,5-Trisphosphate Receptor Inhibitor Antagonizes Hepatic Stellate Cell Activation: A Potential Drug to Treat Liver Fibrosis. Cells 2024; 13:765. [PMID: 38727301 PMCID: PMC11083487 DOI: 10.3390/cells13090765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/18/2024] [Accepted: 04/23/2024] [Indexed: 05/13/2024] Open
Abstract
Liver fibrosis, characterized by excessive extracellular matrix (ECM) deposition, can progress to cirrhosis and increases the risk of liver cancer. Hepatic stellate cells (HSCs) play a pivotal role in fibrosis progression, transitioning from a quiescent to activated state upon liver injury, wherein they proliferate, migrate, and produce ECM. Calcium signaling, involving the inositol 1,4,5-trisphosphate receptor (IP3R), regulates HSC activation. This study investigated the efficacy of a novel IP3R inhibitor, desmethylxestospongin B (dmXeB), in preventing HSC activation. Freshly isolated rat HSCs were activated in vitro in the presence of varying dmXeB concentrations. The dmXeB effectively inhibited HSC proliferation, migration, and expression of fibrosis markers without toxicity to the primary rat hepatocytes or human liver organoids. Furthermore, dmXeB preserved the quiescent phenotype of HSCs marked by retained vitamin A storage. Mechanistically, dmXeB suppressed mitochondrial respiration in activated HSCs while enhancing glycolytic activity. Notably, methyl pyruvate, dimethyl α-ketoglutarate, and nucleoside supplementation all individually restored HSC proliferation despite dmXeB treatment. Overall, dmXeB demonstrates promising anti-fibrotic effects by inhibiting HSC activation via IP3R antagonism without adverse effects on other liver cells. These findings highlight dmXeB as a potential therapeutic agent for liver fibrosis treatment, offering a targeted approach to mitigate liver fibrosis progression and its associated complications.
Collapse
Affiliation(s)
- Natalia Smith-Cortinez
- Department of Gastroenterology and Hepatology, University of Groningen, University Medical Center Groningen (UMCG), 9713 GZ Groningen, The Netherlands
| | - Janette Heegsma
- Department of Gastroenterology and Hepatology, University of Groningen, University Medical Center Groningen (UMCG), 9713 GZ Groningen, The Netherlands
| | - Masa Podunavac
- Department of Chemistry and Biochemistry, University of California, Oakland, CA 94607, USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Oakland, CA 94607, USA
| | - J. César Cardenas
- Department of Chemistry and Biochemistry, University of California, Oakland, CA 94607, USA
- Center for Integrative Biology, Universidad Mayor, Santiago 7510041, Chile
- Buck Institute for Research on Aging, Novato, CA 94945, USA
| | - Klaas Nico Faber
- Department of Gastroenterology and Hepatology, University of Groningen, University Medical Center Groningen (UMCG), 9713 GZ Groningen, The Netherlands
| |
Collapse
|
3
|
Paola EL, Borum A, Podunavac M, Zakarian A. Stereoselective Synthesis of α-Fluoro Carboxylic Acids by Ireland-Claisen Rearrangement. Org Lett 2023; 25:6167-6171. [PMID: 37590527 DOI: 10.1021/acs.orglett.3c01276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Stereoselective synthesis of α-fluoro carboxylic acids by the Ireland-Claisen rearrangement can provide a straightforward approach to this class of compounds. We report a systematic investigation of base-dependent stereocontrol in the Ireland-Claisen rearrangement of α-fluoro esters. For substrates with various substitution patterns, the use of KN(SiMe3)2 in toluene afforded rearrangement products corresponding to the (Z)-enolate intermediate with a practically useful diastereoselectivity and yield. In contrast, lower yields and diastereoselectivity were consistently observed with the use of lithium diisopropylamide (LDA) in tetrahydrofuran (THF).
Collapse
Affiliation(s)
- Elena L Paola
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Alana Borum
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Maša Podunavac
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
4
|
Lee HJ, Gladfelder JJ, Zakarian A. Remote Stereocontrol in the Ireland-Claisen Rearrangement by δ-Alkoxy Group. J Org Chem 2023. [PMID: 37159904 DOI: 10.1021/acs.joc.3c00535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Remote stereocontrol in the Ireland-Claisen rearrangement using a chiral acetonide that serves as internal stereocontrol element is an effective and general method for chirality transfer from a δ-hydroxyl group in the allylic alcohol unit. This strategy circumvents the need for redundant chirality at the α-position allylic alcohol, while simultaneously producing a terminal alkene that can streamline synthetic applications and complex molecule synthesis planning.
Collapse
Affiliation(s)
- Hye Joon Lee
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Joshua J Gladfelder
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
5
|
Li Y, Paola E, Wang Z, Menard G, Zakarian A. Lithium Enolate with a Lithium-Alkyne Interaction in the Enantioselective Construction of Quaternary Carbon Centers: Concise Synthesis of (+)-Goniomitine. Angew Chem Int Ed Engl 2022; 61:e202209987. [PMID: 36251869 PMCID: PMC9798608 DOI: 10.1002/anie.202209987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Indexed: 11/09/2022]
Abstract
We report a method for direct enantioselective alkylation of 3-alkynoic and 2,3-alkendioic acids that form quaternary stereogenic centers, and application of this method to the total enantioselective synthesis of a complex alkaloid (+)-goniomitine. The methods were effective in the alkylation of both 3-alkynoic acids, 2,3-alkendioic acids substrates with a broad range of heterocyclic and functionalized alkyl group substituents. Accompanying crystallographic studies provide mechanistic insight into the structure of well-defined chiral aggregates, highlighting cation-π interactions between lithium and alkyne groups.
Collapse
Affiliation(s)
- Yang Li
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Elena Paola
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Zongheng Wang
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Gabriel Menard
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
- Center for Integrative Biology, Faculty of Sciences, Geroscience Center for Brain Health and Metabolism, Universidad Mayor, Santiago, Chile
| |
Collapse
|
6
|
Li Y, Paola E, Wang Z, Menard G, Zakarian A. Lithium Enolate with a Lithium‐Alkyne Interaction in the Enantioselective Construction of Quaternary Carbon Centers: Concise Synthesis of (+)‐Goniomitine. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202209987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Yang Li
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106 USA
| | - Elena Paola
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106 USA
| | - Zongheng Wang
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106 USA
| | - Gabriel Menard
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106 USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106 USA
- Center for Integrative Biology Faculty of Sciences Geroscience Center for Brain Health and Metabolism Universidad Mayor Santiago Chile
| |
Collapse
|
7
|
Pérez-Liébana I, Juaristi I, González-Sánchez P, González-Moreno L, Rial E, Podunavac M, Zakarian A, Molgó J, Vallejo-Illarramendi A, Mosqueira-Martín L, Lopez de Munain A, Pardo B, Satrústegui J, Del Arco A. A Ca 2+-Dependent Mechanism Boosting Glycolysis and OXPHOS by Activating Aralar-Malate-Aspartate Shuttle, upon Neuronal Stimulation. J Neurosci 2022; 42:3879-3895. [PMID: 35387872 PMCID: PMC9097769 DOI: 10.1523/jneurosci.1463-21.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 12/20/2021] [Accepted: 01/27/2022] [Indexed: 01/18/2023] Open
Abstract
Calcium is an important second messenger regulating a bioenergetic response to the workloads triggered by neuronal activation. In embryonic mouse cortical neurons using glucose as only fuel, activation by NMDA elicits a strong workload (ATP demand)-dependent on Na+ and Ca2+ entry, and stimulates glucose uptake, glycolysis, pyruvate and lactate production, and oxidative phosphorylation (OXPHOS) in a Ca2+-dependent way. We find that Ca2+ upregulation of glycolysis, pyruvate levels, and respiration, but not glucose uptake, all depend on Aralar/AGC1/Slc25a12, the mitochondrial aspartate-glutamate carrier, component of the malate-aspartate shuttle (MAS). MAS activation increases glycolysis, pyruvate production, and respiration, a process inhibited in the presence of BAPTA-AM, suggesting that the Ca2+ binding motifs in Aralar may be involved in the activation. Mitochondrial calcium uniporter (MCU) silencing had no effect, indicating that none of these processes required MCU-dependent mitochondrial Ca2+ uptake. The neuronal respiratory response to carbachol was also dependent on Aralar, but not on MCU. We find that mouse cortical neurons are endowed with a constitutive ER-to-mitochondria Ca2+ flow maintaining basal cell bioenergetics in which ryanodine receptors, RyR2, rather than InsP3R, are responsible for Ca2+ release, and in which MCU does not participate. The results reveal that, in neurons using glucose, MCU does not participate in OXPHOS regulation under basal or stimulated conditions, while Aralar-MAS appears as the major Ca2+-dependent pathway tuning simultaneously glycolysis and OXPHOS to neuronal activation.SIGNIFICANCE STATEMENT Neuronal activation increases cell workload to restore ion gradients altered by activation. Ca2+ is involved in matching increased workload with ATP production, but the mechanisms are still unknown. We find that glycolysis, pyruvate production, and neuronal respiration are stimulated on neuronal activation in a Ca2+-dependent way, independently of effects of Ca2+ as workload inducer. Mitochondrial calcium uniporter (MCU) does not play a relevant role in Ca2+ stimulated pyruvate production and oxygen consumption as both are unchanged in MCU silenced neurons. However, Ca2+ stimulation is blunt in the absence of Aralar, a Ca2+-binding mitochondrial carrier component of Malate-Aspartate Shuttle (MAS). The results suggest that Ca2+-regulated Aralar-MAS activation upregulates glycolysis and pyruvate production, which fuels mitochondrial respiration, through regulation of cytosolic NAD+/NADH ratio.
Collapse
Affiliation(s)
- Irene Pérez-Liébana
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Inés Juaristi
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Paloma González-Sánchez
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Luis González-Moreno
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Eduardo Rial
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas Margarita Salas, Madrid, 28040, Spain
| | - Maša Podunavac
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106
| | - Jordi Molgó
- Université Paris-Saclay, CEA, Institut des Sciences du Vivant Frédéric Joliot, ERL Centre National de la Recherche Scientifique no. 9004, Département Médicaments et Technologies pour la Santé, Service d'Ingénierie Moléculaire pour la Santé, Gif sur Yvette, F-91191, France
| | - Ainara Vallejo-Illarramendi
- IIS Biodonostia-University of the Basque Country, Donostia, Spain; CIBERNED (institute Carlos III), Madrid, Spain; and Department of Neurology, Hospital Universitario Donostia-OSAKIDETZA, San Sebastián, 20014, Spain
| | - Laura Mosqueira-Martín
- IIS Biodonostia-University of the Basque Country, Donostia, Spain; CIBERNED (institute Carlos III), Madrid, Spain; and Department of Neurology, Hospital Universitario Donostia-OSAKIDETZA, San Sebastián, 20014, Spain
| | - Adolfo Lopez de Munain
- IIS Biodonostia-University of the Basque Country, Donostia, Spain; CIBERNED (institute Carlos III), Madrid, Spain; and Department of Neurology, Hospital Universitario Donostia-OSAKIDETZA, San Sebastián, 20014, Spain
| | - Beatriz Pardo
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Araceli Del Arco
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla la Mancha, Toledo, 45071 Spain; and Centro Regional de Investigaciones Biomédicas, Unidad Asociada de Biomedicina, Toledo, 45071, Spain
| |
Collapse
|
8
|
Servent D, Malgorn C, Bernes M, Gil S, Simasotchi C, Hérard AS, Delzescaux T, Thai R, Barbe P, Keck M, Beau F, Zakarian A, Dive V, Molgó J. First evidence that emerging pinnatoxin-G, a contaminant of shellfish, reaches the brain and crosses the placental barrier. Sci Total Environ 2021; 790:148125. [PMID: 34380275 DOI: 10.1016/j.scitotenv.2021.148125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 04/27/2021] [Accepted: 05/26/2021] [Indexed: 06/13/2023]
Abstract
Massive proliferation of some toxic marine dinoflagellates is responsible for the occurrence of harmful algal blooms and the contamination of fish and shellfish worldwide. Pinnatoxins (PnTx) (A-H) comprise an emerging phycotoxin family belonging to the cyclic imine toxin group. Interest has been focused on these lipophilic, fast-acting and highly potent toxins because they are widely found in contaminated shellfish, and can represent a risk for seafood consumers. PnTx display a potent antagonist effect on nicotinic acetylcholine receptors (nAChR), and in this study we assessed in vivo the ability of PnTx-G to cross physiological barriers to reach its molecular target. Radiolabeled [3H]-PnTx-G synthesized with good radiochemical purity and yield retained the high affinity of the natural toxin. Oral gavage or intravenous administration to adult rats and digital autoradiographic analyses revealed the biodistribution and toxicokinetics of [3H]-PnTx-G, which is rapidly cleared from blood, and accumulates in the liver and small intestine. The labeling of peripheral and brain adult/embryo rat tissues highlights its ability to cross the intestinal, blood-brain and placental barriers. High-resolution 3D-imaging and in vitro competition studies on rat embryo sections revealed the specificity of [3H]-PnTx-G binding and its selectivity for muscle and neuronal nAChR subtypes (such as α7 subtype). The use of a human perfused cotyledon model and mass spectrometry analyses disclosed that PnTx-G crosses the human placental barrier. The increasing worldwide occurrence of both the dinoflagellate Vulcanodinium rugosum and PnTx-contaminated shellfish, due to climate warming, raises concerns about the potential adverse impact that exposure to pinnatoxins may have for human health.
Collapse
Affiliation(s)
- Denis Servent
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France.
| | - Carole Malgorn
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France
| | - Mylène Bernes
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France
| | - Sophie Gil
- Université de Paris, UMR-S1139, Faculté de Pharmacie de Paris, France
| | | | - Anne-Sophie Hérard
- Université Paris-Saclay, UMR9199, CNRS, CEA, MIRCen, Fontenay-aux-Roses, France
| | - Thierry Delzescaux
- Université Paris-Saclay, UMR9199, CNRS, CEA, MIRCen, Fontenay-aux-Roses, France
| | - Robert Thai
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France
| | - Peggy Barbe
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France
| | - Mathilde Keck
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France
| | - Fabrice Beau
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France
| | - Armen Zakarian
- University of California, Santa Barbara, Department of Chemistry and Biochemistry, CA 93106-9510, USA
| | - Vincent Dive
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France
| | - Jordi Molgó
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, ERL CNRS 9004, F-91191 Gif sur Yvette, France.
| |
Collapse
|
9
|
Podunavac M, Mailyan AK, Jackson JJ, Lovy A, Farias P, Huerta H, Molgó J, Cardenas C, Zakarian A. Scalable Total Synthesis, IP3R Inhibitory Activity of Desmethylxestospongin B, and Effect on Mitochondrial Function and Cancer Cell Survival. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Maša Podunavac
- Department of Chemistry and Biochemistry University of California Santa Barbara Santa Barbara CA 93106 USA
| | - Artur K. Mailyan
- Department of Chemistry and Biochemistry University of California Santa Barbara Santa Barbara CA 93106 USA
| | - Jeffrey J. Jackson
- Department of Chemistry and Biochemistry University of California Santa Barbara Santa Barbara CA 93106 USA
| | - Alenka Lovy
- Center for Integrative Biology Faculty of Sciences Geroscience Center for Brain Health and Metabolism Universidad Mayor Santiago Chile
| | - Paula Farias
- Center for Integrative Biology Faculty of Sciences Geroscience Center for Brain Health and Metabolism Universidad Mayor Santiago Chile
| | - Hernan Huerta
- Center for Integrative Biology Faculty of Sciences Geroscience Center for Brain Health and Metabolism Universidad Mayor Santiago Chile
| | - Jordi Molgó
- Université Paris-Saclay CEA Institut des Sciences du Vivant Frédéric Joliot ERL CNRS n 9004 Département Médicaments et Technologies pour la Santé Service d'Ingéniere Moléculaire pour Santé (SIMoS) Batiment 152, Point courrier 24 91191 Gif-sur-Yvette France
| | - Cesar Cardenas
- Department of Chemistry and Biochemistry University of California Santa Barbara Santa Barbara CA 93106 USA
- Center for Integrative Biology Faculty of Sciences Geroscience Center for Brain Health and Metabolism Universidad Mayor Santiago Chile
- The Buck Institute for Research on Aging Novato CA USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry University of California Santa Barbara Santa Barbara CA 93106 USA
| |
Collapse
|
10
|
Podunavac M, Mailyan AK, Jackson JJ, Lovy A, Farias P, Huerta H, Molgó J, Cardenas C, Zakarian A. Scalable Total Synthesis, IP3R Inhibitory Activity of Desmethylxestospongin B, and Effect on Mitochondrial Function and Cancer Cell Survival. Angew Chem Int Ed Engl 2021; 60:11278-11282. [PMID: 33751770 DOI: 10.1002/anie.202102259] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Indexed: 11/05/2022]
Abstract
The scalable synthesis of the oxaquinolizidine marine natural product desmethylxestospongin B is based on the early application of Ireland-Claisen rearrangement, macrolactamization, and a late-stage installation of the oxaquinolizidine units by lactam reduction. The synthesis serves as the source of material to investigate calcium signaling and its effect on mitochondrial metabolism in various cell types, including cancer cells.
Collapse
Affiliation(s)
- Maša Podunavac
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Artur K Mailyan
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Jeffrey J Jackson
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Alenka Lovy
- Center for Integrative Biology, Faculty of Sciences, Geroscience Center for Brain Health and Metabolism, Universidad Mayor, Santiago, Chile
| | - Paula Farias
- Center for Integrative Biology, Faculty of Sciences, Geroscience Center for Brain Health and Metabolism, Universidad Mayor, Santiago, Chile
| | - Hernan Huerta
- Center for Integrative Biology, Faculty of Sciences, Geroscience Center for Brain Health and Metabolism, Universidad Mayor, Santiago, Chile
| | - Jordi Molgó
- Université Paris-Saclay, CEA, Institut des Sciences du Vivant Frédéric Joliot, ERL CNRS n 9004, Département Médicaments et Technologies pour la Santé, Service d'Ingéniere Moléculaire pour Santé (SIMoS), Batiment 152, Point courrier 24, 91191, Gif-sur-Yvette, France
| | - Cesar Cardenas
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.,Center for Integrative Biology, Faculty of Sciences, Geroscience Center for Brain Health and Metabolism, Universidad Mayor, Santiago, Chile.,The Buck Institute for Research on Aging, Novato, CA, USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| |
Collapse
|
11
|
Abstract
A method has been developed for the α-tertiary alkylation of zirconium enolates of N-(arylacetyl)oxazolidinones. This reaction directly installs an all-carbon quaternary center vicinal to a benzylic tertiary carbon in a highly diastereoselective manner.
Collapse
Affiliation(s)
- Eunjae Shim
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510, USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510, USA
| |
Collapse
|
12
|
Aráoz R, Barnes P, Séchet V, Delepierre M, Zinn-Justin S, Molgó J, Zakarian A, Hess P, Servent D. Cyclic imine toxins survey in coastal european shellfish samples: Bioaccumulation and mode of action of 28-O-palmitoyl ester of pinnatoxin-G. first report of portimine-A bioaccumulation. Harmful Algae 2020; 98:101887. [PMID: 33129465 PMCID: PMC7657664 DOI: 10.1016/j.hal.2020.101887] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 07/11/2020] [Accepted: 07/24/2020] [Indexed: 05/12/2023]
Abstract
Cyclic imine toxins exhibit fast acting neurotoxicity and lethality by respiratory arrest in mice explained by their potent antagonistic activity against muscular nicotinic acetylcholine receptors. We performed a survey of gymnodimine-A, 13-desmethyl spirolide-C, 13,19-didesmethyl spirolide-C, 20-methyl spirolide-G, pinnatoxin-A, pinnatoxin-G, portimine-A and 28-O-palmitoyl ester of pinnatoxin-G in 36 shellfish samples collected in coastal areas of 8 European countries using a microplate receptor binding assay and UPLC-MS/MS for toxin identification and quantification. The major toxins found in these samples were pinnatoxin-G, 20-methyl spirolide-G, 13-desmethyl spirolide-C, gymnodimine-A and portimine-A. Traces of 13,19-didesmethyl spirolide-C, pinnatoxin-A and 28-O-palmitoyl ester of pinnatoxin-G were also detected. The rapid death of mice was correlated with higher pinnatoxin-G concentrations in mussel digestive gland extracts injected intraperitoneally. Our survey included nontoxic control samples that were found to contain moderate to trace amounts of several cyclic imine toxins. Shellfish may bioaccumulate not only cyclic imine toxins but also a large number of acyl derivatives as a product of metabolic transformation of these neurotoxins. This is the first report in which portimine-A and 28-O-palmitoyl ester of pinnatoxin-G were detected in shellfish extracts from digestive glands of mussels collected in Ingril lagoon. The bioaccumulation of portimine-A is particularly of concern because it is cytotoxic and is able to induce apotosis. The mode of action of 28-O-palmitoyl ester of pinnatoxin-G was studied by receptor binding-assay and by two-electrode voltage clamp electrophysiology. The antagonistic behavior of the acylated pinnatoxin-G towards nicotinic acetylcholine receptor of muscle type is shown here for the first time. Since cyclic imine toxins are not regulated further monitoring of these emerging toxins is needed to improve evidence gathering of their occurrence in shellfish commercialized for human consumption in Europe given their potent antagonism against muscle and neuronal nicotinic acetylcholine receptors.
Collapse
Affiliation(s)
- Rómulo Aráoz
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, France; CNRS, ERL9004, 91191, Gif-sur-Yvette, France.
| | - Paul Barnes
- Agri-food and Biosciences Institute, Veterinary Science Division, Stoney Road, Belfast BT4 3SD, Northern Ireland, United Kingdom
| | - Véronique Séchet
- Ifremer, Centre Atlantique, Laboratoire Phycotoxines, 44311 Nantes Cedex, France
| | - Muriel Delepierre
- Institut Pasteur, Department of Structural Biology and Chemistry CNRS, UMR3528, Paris France
| | - Sophie Zinn-Justin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud, Université Paris-Saclay, Gif- sur -Yvette Cedex, France
| | - Jordi Molgó
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, France; CNRS, ERL9004, 91191, Gif-sur-Yvette, France
| | - Armen Zakarian
- University California Santa Barbara, Dept Chem & Biochem, Santa Barbara, CA 93106 United States
| | - Philipp Hess
- Ifremer, Centre Atlantique, Laboratoire Phycotoxines, 44311 Nantes Cedex, France
| | - Denis Servent
- Université Paris Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, France; CNRS, ERL9004, 91191, Gif-sur-Yvette, France
| |
Collapse
|
13
|
Cardenas C, Lovy A, Silva-Pavez E, Urra F, Mizzoni C, Ahumada-Castro U, Bustos G, Jaňa F, Cruz P, Farias P, Mendoza E, Huerta H, Murgas P, Hunter M, Rios M, Cerda O, Georgakoudi I, Zakarian A, Molgó J, Foskett JK. Cancer cells with defective oxidative phosphorylation require endoplasmic reticulum-to-mitochondria Ca 2+ transfer for survival. Sci Signal 2020; 13:13/640/eaay1212. [PMID: 32665411 DOI: 10.1126/scisignal.aay1212] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Spontaneous Ca2+ signaling from the InsP3R intracellular Ca2+ release channel to mitochondria is essential for optimal oxidative phosphorylation (OXPHOS) and ATP production. In cells with defective OXPHOS, reductive carboxylation replaces oxidative metabolism to maintain amounts of reducing equivalents and metabolic precursors. To investigate the role of mitochondrial Ca2+ uptake in regulating bioenergetics in these cells, we used OXPHOS-competent and OXPHOS-defective cells. Inhibition of InsP3R activity or mitochondrial Ca2+ uptake increased α-ketoglutarate (αKG) abundance and the NAD+/NADH ratio, indicating that constitutive endoplasmic reticulum (ER)-to-mitochondria Ca2+ transfer promoted optimal αKG dehydrogenase (αKGDH) activity. Reducing mitochondrial Ca2+ inhibited αKGDH activity and increased NAD+, which induced SIRT1-dependent autophagy in both OXPHOS-competent and OXPHOS-defective cells. Whereas autophagic flux in OXPHOS-competent cells promoted cell survival, it was impaired in OXPHOS-defective cells because of inhibition of autophagosome-lysosome fusion. Inhibition of αKGDH and impaired autophagic flux in OXPHOS-defective cells resulted in pronounced cell death in response to interruption of constitutive flux of Ca2+ from ER to mitochondria. These results demonstrate that mitochondria play a fundamental role in maintaining bioenergetic homeostasis of both OXPHOS-competent and OXPHOS-defective cells, with Ca2+ regulation of αKGDH activity playing a pivotal role. Inhibition of ER-to-mitochondria Ca2+ transfer may represent a general therapeutic strategy against cancer cells regardless of their OXPHOS status.
Collapse
Affiliation(s)
- Cesar Cardenas
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile. .,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile.,Buck Institute for Research on Aging, Novato, CA 94945, USA.,Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Alenka Lovy
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile.,Department of Neuroscience, Center for Neuroscience Research, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Eduardo Silva-Pavez
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile
| | - Felix Urra
- Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile.,Program of Molecular and Clinical Pharmacology, Institute of Biomedical Science, Universidad de Chile, Santiago 8380453, Chile
| | - Craig Mizzoni
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA
| | - Ulises Ahumada-Castro
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile
| | - Galdo Bustos
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile
| | - Fabian Jaňa
- Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile.,Universidad de Aysén, Coyhaique, 5952073, 8380453, Chile
| | - Pablo Cruz
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile
| | - Paula Farias
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile
| | - Elizabeth Mendoza
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile
| | - Hernan Huerta
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile
| | - Paola Murgas
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile
| | - Martin Hunter
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA
| | - Melany Rios
- Center for Integrative Biology, Faculty of Sciences, Universidad Mayor, Santiago 8580745, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago 8580745, Chile
| | - Oscar Cerda
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Santiago, Chile.,The Wound Repair, Treatment and Health (WoRTH), Santiago, Chile
| | - Irene Georgakoudi
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Jordi Molgó
- Université Paris-Saclay, CEA, Institut des Sciences du Vivant Frédéric Joliot, ERL CNRS n° 9004, Département Médicaments et Technologies pour la Santé, Service d'Ingénierie Moléculaire pour la Santé (SIMoS), bâtiment 152, Point courrier 24, F-91191 Gif sur Yvette, France
| | - J Kevin Foskett
- Departments of Physiology and Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
14
|
Lacharity JJ, Mailyan AK, Chen KY, Zakarian A. Concise Synthesis of (+)-[ 13 C 4 ]-Anatoxin-a by Dynamic Kinetic Resolution of a Cyclic Iminium Ion. Angew Chem Int Ed Engl 2020; 59:11364-11368. [PMID: 32304178 PMCID: PMC7409530 DOI: 10.1002/anie.202004464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/17/2020] [Indexed: 11/11/2022]
Abstract
An asymmetric total synthesis of [13 C4 ]-anatoxin-a ([13 C4 ]-1) has been developed from commercially available ethyl [13 C4 ]-acetoacetate ([13 C4 ]-15). The unique requirements associated with isotope incorporation inspired a new, robust, and highly scalable route, providing access to 0.110 g of this internal standard for use in the detection and precise quantification of anatoxin-a in freshwater. A highlight of the synthesis is a method that leverages a cyclic iminium ion racemization to achieve dynamic kinetic resolution in an enantioselective Morita-Baylis-Hillman (MBH) cyclization.
Collapse
Affiliation(s)
- Jacob J Lacharity
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106-9510, USA
| | - Artur K Mailyan
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106-9510, USA
| | - Karen Y Chen
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106-9510, USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106-9510, USA
| |
Collapse
|
15
|
Lacharity JJ, Mailyan AK, Chen KY, Zakarian A. Concise Synthesis of (+)‐[
13
C
4
]‐Anatoxin‐a by Dynamic Kinetic Resolution of a Cyclic Iminium Ion. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202004464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jacob J. Lacharity
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106-9510 USA
| | - Artur K. Mailyan
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106-9510 USA
| | - Karen Y. Chen
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106-9510 USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106-9510 USA
| |
Collapse
|
16
|
Servent D, Creuzet S, Malgorn C, Dive V, Zakarian A, Molgó J. Pinnatoxins, an emergent class of marine toxins interacting with nAChRs. Pharmacological characterization, biodistribution and musculo-skeletal effect of these neurotoxic agents. Toxicon 2020. [DOI: 10.1016/j.toxicon.2019.10.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
17
|
Gladfelder JJ, Ghosh S, Podunavac M, Cook AW, Ma Y, Woltornist RA, Keresztes I, Hayton TW, Collum DB, Zakarian A. Enantioselective Alkylation of 2-Alkylpyridines Controlled by Organolithium Aggregation. J Am Chem Soc 2019; 141:15024-15028. [PMID: 31460756 DOI: 10.1021/jacs.9b08659] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Direct enantioselective α-alkylation of 2-alkylpyridines provides access to chiral pyridines via an operationally simple protocol that obviates the need for prefunctionalization or preactivation of the substrate. The alkylation is accomplished using chiral lithium amides as noncovalent stereodirecting auxiliaries. Crystallographic and solution NMR studies provide insight into the structure of well-defined chiral aggregates in which a lithium amide reagent directs asymmetric alkylation.
Collapse
Affiliation(s)
- Joshua J Gladfelder
- Department of Chemistry and Biochemistry , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| | - Santanu Ghosh
- Department of Chemistry and Biochemistry , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| | - Maša Podunavac
- Department of Chemistry and Biochemistry , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| | - Andrew W Cook
- Department of Chemistry and Biochemistry , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| | - Yun Ma
- Department of Chemistry and Biochemistry , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| | - Ryan A Woltornist
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
| | - Ivan Keresztes
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
| | - Trevor W Hayton
- Department of Chemistry and Biochemistry , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| | - David B Collum
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| |
Collapse
|
18
|
Lacharity JJ, Zakarian A. Evolution of a Chemical Strategy Toward the Synthesis of Unsymmetrically Oxidized Nuphar Alkaloids. Synlett 2019. [DOI: 10.1055/s-0037-1611866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Here we describe the frustrations, joys, and unexpected turns experienced in our journey toward a successful strategy directed at the total synthesis of unsymmetrically oxidized Nuphar thioalkaloids. While many adjustments were made to our initial synthesis plan, our general approach to the construction of the central bis(spirothiolane) moiety remained unchanged. Specifically, each iteration of our synthesis design involved the formation of the thiaspirane motif through the stereodivergent coupling of a thietane with a metal carbenoid, followed by a Stevens-type rearrangement of the resulting sulfonium ylide.1 Introduction2 First-Generation Strategy3 Second-Generation Strategy4 Third-Generation Strategy5 Conclusion
Collapse
|
19
|
Benoit E, Couesnon A, Lindovsky J, Iorga BI, Aráoz R, Servent D, Zakarian A, Molgó J. Synthetic Pinnatoxins A and G Reversibly Block Mouse Skeletal Neuromuscular Transmission In Vivo and In Vitro. Mar Drugs 2019; 17:md17050306. [PMID: 31137661 PMCID: PMC6562580 DOI: 10.3390/md17050306] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 05/17/2019] [Accepted: 05/21/2019] [Indexed: 12/14/2022] Open
Abstract
Pinnatoxins (PnTXs) A-H constitute an emerging family belonging to the cyclic imine group of phycotoxins. Interest has been focused on these fast-acting and highly-potent toxins because they are widely found in contaminated shellfish. Despite their highly complex molecular structure, PnTXs have been chemically synthetized and demonstrated to act on various nicotinic acetylcholine receptor (nAChR) subtypes. In the present work, PnTX-A, PnTX-G and analogue, obtained by chemical synthesis with a high degree of purity (>98%), have been studied in vivo and in vitro on adult mouse and isolated nerve-muscle preparations expressing the mature muscle-type (α1)2β1δε nAChR. The results show that PnTX-A and G acted on the neuromuscular system of anesthetized mice and blocked the compound muscle action potential (CMAP) in a dose- and time-dependent manner, using a minimally invasive electrophysiological method. The CMAP block produced by both toxins in vivo was reversible within 6–8 h. PnTX-A and G, applied to isolated extensor digitorum longus nerve-muscle preparations, blocked reversibly isometric twitches evoked by nerve stimulation. The action of PnTX-A was reversed by 3,4-diaminopyridine. Both toxins exerted no direct action on muscle fibers, as revealed by direct muscle stimulation. PnTX-A and G blocked synaptic transmission at mouse neuromuscular junctions and PnTX-A amino ketone analogue (containing an open form of the imine ring) had no effect on neuromuscular transmission. These results indicate the importance of the cyclic imine for interacting with the adult mammalian muscle-type nAChR. Modeling and docking studies revealed molecular determinants responsible for the interaction of PnTXs with the muscle-type nAChR.
Collapse
Affiliation(s)
- Evelyne Benoit
- Commissariat à l'Energie Atomique et aux énergies Alternatives (CEA), Institut des Sciences du Vivant Frédéric Joliot, Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), CEA de Saclay, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France.
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Paris-Saclay (Neuro-PSI), UMR 9197 CNRS/Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
| | - Aurélie Couesnon
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Paris-Saclay (Neuro-PSI), UMR 9197 CNRS/Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
| | - Jiri Lindovsky
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Paris-Saclay (Neuro-PSI), UMR 9197 CNRS/Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
| | - Bogdan I Iorga
- Centre National de la Recherche Scientifique (CNRS), Institut de Chimie des Substances Naturelles, UPR 2301, Labex LERMIT, F-91198 Gif-sur-Yvette, France.
| | - Rómulo Aráoz
- Commissariat à l'Energie Atomique et aux énergies Alternatives (CEA), Institut des Sciences du Vivant Frédéric Joliot, Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), CEA de Saclay, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France.
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Paris-Saclay (Neuro-PSI), UMR 9197 CNRS/Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
| | - Denis Servent
- Commissariat à l'Energie Atomique et aux énergies Alternatives (CEA), Institut des Sciences du Vivant Frédéric Joliot, Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), CEA de Saclay, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France.
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA.
| | - Jordi Molgó
- Commissariat à l'Energie Atomique et aux énergies Alternatives (CEA), Institut des Sciences du Vivant Frédéric Joliot, Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), CEA de Saclay, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France.
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Paris-Saclay (Neuro-PSI), UMR 9197 CNRS/Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
| |
Collapse
|
20
|
Yu K, Miao B, Wang W, Zakarian A. Direct Enantioselective and Regioselective Alkylation of β,γ-Unsaturated Carboxylic Acids with Chiral Lithium Amides as Traceless Auxiliaries. Org Lett 2019; 21:1930-1934. [PMID: 30835486 DOI: 10.1021/acs.orglett.9b00587] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Efficient asymmetric alkylation of β,γ-unsaturated carboxylic acids without prior functionalization is enabled by chiral lithium amides. Enantioselectivity is imparted by a putative mixed lithium amide-enediolate aggregate that acts a traceless auxiliary formed in situ, allowing for a direct asymmetric alkylation and a simple recovery of the chiral reagent.
Collapse
Affiliation(s)
- Kai Yu
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| | - Bukeyan Miao
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| | - Wenqi Wang
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| |
Collapse
|
21
|
Molgó J, Amar M, Araoz R, Benoit E, Iorga B, Yasumoto T, Zakarian A, Servent D. The cyclic imine family of dinoflagellate toxins targeting nicotinic acetylcholine receptors. Toxicon 2019. [DOI: 10.1016/j.toxicon.2018.10.080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
22
|
Fournier J, Chen K, Mailyan AK, Jackson JJ, Buckman BO, Emayan K, Yuan S, Rajagopalan R, Misialek S, Adler M, Blaesse M, Griessner A, Zakarian A. Total Synthesis of Covalent Cysteine Protease Inhibitor N-Desmethyl Thalassospiramide C and Crystallographic Evidence for Its Mode of Action. Org Lett 2019; 21:508-512. [DOI: 10.1021/acs.orglett.8b03821] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jeremy Fournier
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93111, United States
| | - Karen Chen
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93111, United States
| | - Artur K. Mailyan
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93111, United States
| | - Jeffrey J. Jackson
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93111, United States
| | - Brad O. Buckman
- Blade Therapeutics, 442 Littlefield Avenue, South San Francisco, California 94080, United States
| | - Kumar Emayan
- Bayside Pharma, 2600 Hilltop Drive, Richmond, California 94806, United States
| | - Shendong Yuan
- Bayside Pharma, 2600 Hilltop Drive, Richmond, California 94806, United States
| | - Ravi Rajagopalan
- Blade Therapeutics, 442 Littlefield Avenue, South San Francisco, California 94080, United States
| | - Shawn Misialek
- Blade Therapeutics, 442 Littlefield Avenue, South San Francisco, California 94080, United States
| | - Marc Adler
- ChemPartner, 280 Utah Avenue Suite 100, South San Francisco, California 94080, United States
| | - Michael Blaesse
- Proteros Biostructures GmbH, Bunsenstraße 7 a, 82152 Planegg-Martinsried, Germany
| | - Andreas Griessner
- Proteros Biostructures GmbH, Bunsenstraße 7 a, 82152 Planegg-Martinsried, Germany
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93111, United States
| |
Collapse
|
23
|
Kearney SE, Zahoránszky-Kőhalmi G, Brimacombe KR, Henderson MJ, Lynch C, Zhao T, Wan K, Itkin Z, Dillon C, Shen M, Cheff D, Lee T, Bougie D, Cheng K, Coussens N, Dorjsuren D, Eastman R, Huang R, Iannotti M, Karavadhi S, Klumpp-Thomas C, Roth J, Sakamuru S, Sun W, Titus S, Yasgar A, Zhang YQ, Zhao J, Andrade R, Brown MK, Burns N, Cha JK, Mevers E, Clardy J, Clement J, Crooks P, Cuny G, Ganor J, Moreno J, Morrill L, Picazo E, Susick R, Garg N, Goess B, Grossman R, Hughes C, Johnston J, Joullie M, Kinghorn AD, Kingston D, Krische M, Kwon O, Maimone T, Majumdar S, Maloney K, Mohamed E, Murphy B, Nagorny P, Olson D, Overman L, Brown L, Snyder J, Porco J, Rivas F, Ross S, Sarpong R, Sharma I, Shaw J, Xu Z, Shen B, Shi W, Stephenson C, Verano A, Tan D, Tang Y, Taylor R, Thomson R, Vosburg D, Wu J, Wuest W, Zakarian A, Zhang Y, Ren T, Zuo Z, Inglese J, Michael S, Simeonov A, Zheng W, Shinn P, Jadhav A, Boxer M, Hall MD, Xia M, Guha R, Rohde JM. Canvass: A Crowd-Sourced, Natural-Product Screening Library for Exploring Biological Space. ACS Cent Sci 2018; 4:1727-1741. [PMID: 30648156 PMCID: PMC6311695 DOI: 10.1021/acscentsci.8b00747] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Indexed: 05/20/2023]
Abstract
Natural products and their derivatives continue to be wellsprings of nascent therapeutic potential. However, many laboratories have limited resources for biological evaluation, leaving their previously isolated or synthesized compounds largely or completely untested. To address this issue, the Canvass library of natural products was assembled, in collaboration with academic and industry researchers, for quantitative high-throughput screening (qHTS) across a diverse set of cell-based and biochemical assays. Characterization of the library in terms of physicochemical properties, structural diversity, and similarity to compounds in publicly available libraries indicates that the Canvass library contains many structural elements in common with approved drugs. The assay data generated were analyzed using a variety of quality control metrics, and the resultant assay profiles were explored using statistical methods, such as clustering and compound promiscuity analyses. Individual compounds were then sorted by structural class and activity profiles. Differential behavior based on these classifications, as well as noteworthy activities, are outlined herein. One such highlight is the activity of (-)-2(S)-cathafoline, which was found to stabilize calcium levels in the endoplasmic reticulum. The workflow described here illustrates a pilot effort to broadly survey the biological potential of natural products by utilizing the power of automation and high-throughput screening.
Collapse
Affiliation(s)
- Sara E. Kearney
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Gergely Zahoránszky-Kőhalmi
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Kyle R. Brimacombe
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Mark J. Henderson
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Caitlin Lynch
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Tongan Zhao
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Kanny
K. Wan
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
- Department
of Chemistry, Harvey Mudd College, 301 Platt Boulevard, Claremont, California 91711, United States
| | - Zina Itkin
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Christopher Dillon
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Min Shen
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Dorian
M. Cheff
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Tobie
D. Lee
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Danielle Bougie
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Ken Cheng
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Nathan
P. Coussens
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Dorjbal Dorjsuren
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Richard
T. Eastman
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Ruili Huang
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Michael
J. Iannotti
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Surendra Karavadhi
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Carleen Klumpp-Thomas
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Jacob
S. Roth
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Srilatha Sakamuru
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Wei Sun
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Steven
A. Titus
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Adam Yasgar
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Ya-Qin Zhang
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Jinghua Zhao
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Rodrigo
B. Andrade
- Department
of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - M. Kevin Brown
- Department
of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Noah
Z. Burns
- Department
of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, United States
| | - Jin K. Cha
- Department
of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Emily
E. Mevers
- Department
of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, United States
| | - Jon Clardy
- Department
of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, United States
| | - Jason
A. Clement
- Natural
Products Discovery Institute, Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, Pennsylvania 18902, United States
| | - Peter
A. Crooks
- University
of Arkansas for Medical Sciences, 4301 West Markham Street 522, Little Rock, Arkansas 72205, United States
| | - Gregory
D. Cuny
- Department
of Pharmacological and Pharmaceutical Sciences, University of Houston, 4849 Calhoun Road, Houston, Texas 77204, United
States
| | - Jake Ganor
- Diamond
Age Corp., 344 East Louisiana
Street, McKinney, Texas 75069, United States
| | - Jesus Moreno
- Department
of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | - Lucas
A. Morrill
- Department
of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | - Elias Picazo
- Department
of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | - Robert
B. Susick
- Department
of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | - Neil
K. Garg
- Department
of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | - Brian
C. Goess
- Department
of Chemistry, Furman University, 3300 Poinsett Highway, Greenville, South Carolina 29613, United States
| | - Robert
B. Grossman
- Department
of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Chambers
C. Hughes
- Scripps
Institution of Oceanography, UCSD, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Jeffrey
N. Johnston
- Department
of Chemistry, Vanderbilt University, 7330 Stevenson Center, Nashville, Tennessee 37235, United States
| | - Madeleine
M. Joullie
- Department
of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - A. Douglas Kinghorn
- College
of Pharmacy, The Ohio State University, 500 West 12th Avenue, Columbus, Ohio 43210, United States
| | - David
G.I. Kingston
- Department
of Chemistry, Virginia Tech, 900 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Michael
J. Krische
- Chemistry
Department, The University of Texas at Austin, 105 East 24th Street STOP A5300, Austin, Texas 78712, United States
| | - Ohyun Kwon
- Department
of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | - Thomas
J. Maimone
- Department
of Chemistry, University of California Berkeley, 826 Latimer Hall, Berkeley, California 94720, United States
| | - Susruta Majumdar
- Department
of Molecular Pharmacology and Neurology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, United States
- Center for
Clinical Pharmacology, St Louis College
of Pharmacy and Washington University School of Medicine, 2 Pharmacy Place, St. Louis, Missouri 63110, United States
| | - Katherine
N. Maloney
- Department
of Chemistry, Point Loma Nazarene University, 3900 Lomaland Drive, San Diego, California 92106, United States
| | - Enas Mohamed
- University
of Mississippi School of Pharmacy, 2500 North State Street, Jackson, Mississippi 39216, United States
| | - Brian
T. Murphy
- College
of Pharmacy, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 900 South Ashland Avenue, Chicago, Illinois 60607, United States
| | - Pavel Nagorny
- Department
of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - David
E. Olson
- Department
of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
- School of
Medicine, Department of Biochemistry and Molecular Medicine, University of California, Davis, 2700 Stockton Boulevard, Suite 2102, Sacramento, California 95817, United States
- Center for
Neuroscience, University of California,
Davis, 1544 Newton Court, Davis, California 95618, United States
| | - Larry
E. Overman
- Department
of Chemistry, University of California,
Irvine, Irvine, California 92697, United States
| | - Lauren
E. Brown
- Department
of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - John
K. Snyder
- Department
of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - John
A. Porco
- Department
of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - Fatima Rivas
- Department
of Chemical Biology and Therapeutics, St.
Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, Tennessee 38105, United States
| | - Samir
A. Ross
- University
of Mississippi School of Pharmacy, 2500 North State Street, Jackson, Mississippi 39216, United States
| | - Richmond Sarpong
- Department
of Chemistry, University of California Berkeley, 841-A Latimer Hall, Berkeley, California 94720, United States
| | - Indrajeet Sharma
- Department
of Chemistry and Biochemistry, and Institute of Natural Products and
Research Technologies, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Jared
T. Shaw
- Department
of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Zhengren Xu
- Department
of Chemistry, Florida Campus, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United States
| | - Ben Shen
- Department
of Chemistry, Florida Campus, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United States
| | - Wei Shi
- Department
of Chemistry and Biochemistry, University
of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Corey
R.J. Stephenson
- Department
of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Alyssa
L. Verano
- Pharmacology
Graduate Program, Weill Cornell Graduate School of Medical Sciences, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, United States
| | - Derek
S. Tan
- Pharmacology
Graduate Program, Weill Cornell Graduate School of Medical Sciences, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, United States
- Chemical
Biology Program, Sloan Kettering Institute and Tri-Institutional Research
Program, Memorial Sloan Kettering Cancer
Center, 1275 York Avenue, New York, New York 10065, United States
| | - Yi Tang
- Department
of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | - Richard
E. Taylor
- Department
of Chemistry and Biochemistry and the Warren Family Research Center
for Drug Discovery and Development, University
of Notre Dame, 305 McCourtney
Hall, Notre Dame, Indiana 46556, United States
| | - Regan
J. Thomson
- Department
of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - David
A. Vosburg
- Department
of Chemistry, Harvey Mudd College, 301 Platt Boulevard, Claremont, California 91711, United States
| | - Jimmy Wu
- Department
of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - William
M. Wuest
- Department
of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
- Emory Antibiotic
Resistance Center, Emory University School
of Medicine, 201 Dowman
Drive, Atlanta, Georgia 30322, United States
| | - Armen Zakarian
- Santa
Barbara
Department of Chemistry and Biochemistry, University of California, Santa
Barbara, California 93106, United States
| | - Yufeng Zhang
- School of
Pharmacy, Faculty of Medicine, The Chinese
University of Hong Kong, Sha Tin, New Territories, Hong Kong SAR
| | - Tianjing Ren
- School of
Pharmacy, Faculty of Medicine, The Chinese
University of Hong Kong, Sha Tin, New Territories, Hong Kong SAR
| | - Zhong Zuo
- School of
Pharmacy, Faculty of Medicine, The Chinese
University of Hong Kong, Sha Tin, New Territories, Hong Kong SAR
| | - James Inglese
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Sam Michael
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Anton Simeonov
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Wei Zheng
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Paul Shinn
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Ajit Jadhav
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Matthew
B. Boxer
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Matthew D. Hall
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
- Phone: 301-480-9928. Fax: 301-217-5736.
E-mail:
| | - Menghang Xia
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Rajarshi Guha
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
| | - Jason M. Rohde
- National
Center for Advancing Translational Sciences, National Institutes of
Health, 9800 Medical Center Drive, Rockville, Maryland 20850, United States
- Phone: 301-319-9272. Fax: 301-319-9449. E-mail:
| |
Collapse
|
24
|
Affiliation(s)
- Maša Podunavac
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Jacob J. Lacharity
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Kerry E. Jones
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
25
|
Abstract
Protecting-group-free total synthesis of (+)-guadinomic acid is reported using δ-valerolactone as a readily available starting material. The protocol utilizes the recent hydroxyl-directed guanidylation of unactivated alkenes as an approach for direct stereoselective incorporation of the guanidine unit furnishing the natural product in 7 steps.
Collapse
Affiliation(s)
- Bradley T Reid
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93110 , United States
| | - Artur K Mailyan
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93110 , United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93110 , United States
| |
Collapse
|
26
|
Mailyan AK, Chen JL, Li W, Keller AA, Sternisha SM, Miller BG, Zakarian A. Short Total Synthesis of [ 15N 5]-Cylindrospermopsins from 15NH 4Cl Enables Precise Quantification of Freshwater Cyanobacterial Contamination. J Am Chem Soc 2018; 140:6027-6032. [PMID: 29672038 PMCID: PMC6312099 DOI: 10.1021/jacs.8b03071] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fresh water cyanobacterial algal blooms represent a major health risk because these organisms produce cylindrospermopsin, a toxic, structurally complex, zwitterionic uracil-guanidine alkaloid recognized by the EPA as a dangerous drinking water contaminant. At present, the ability to detect and quantify the presence of cylindrospermospin in water samples is severely hampered by the lack of an isotopically labeled standard for analytical mass spectrometry. Herein, we present a concise, scaled total synthesis of 15N cylindrospermosin from 15N ammonium chloride, which leverages a unique stereoselective intramolecular double conjugate addition step to assemble the tricyclic guanidine core. In addition to providing the first pure isotopically labeled probe for precise quantification of this potent biotoxin in fresh water sources, our results demonstrate how unique constraints associated with isotope incorporation compel novel solutions to synthesis design.
Collapse
Affiliation(s)
- Artur K Mailyan
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93110 , United States
| | - Joanna L Chen
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93110 , United States
| | - Weiwei Li
- Bren School of Environmental Science and Management , University of California , Santa Barbara , California 93106 , United States
| | - Arturo A Keller
- Bren School of Environmental Science and Management , University of California , Santa Barbara , California 93106 , United States
| | - Shawn M Sternisha
- Department of Chemistry and Biochemistry , Florida State University , Tallahassee , Florida 32310 , United States
| | - Brian G Miller
- Department of Chemistry and Biochemistry , Florida State University , Tallahassee , Florida 32310 , United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93110 , United States
| |
Collapse
|
27
|
Abstract
Guest editors Louis Fensterbank, Shuanhu Gao and Armen Zakarian introduce this Organic Chemistry Frontiers themed collection entitled “Synthetic approaches to natural products via catalytic processes”.
Collapse
|
28
|
Lacharity JJ, Fournier J, Lu P, Mailyan AK, Herrmann AT, Zakarian A. Total Synthesis of Unsymmetrically Oxidized Nuphar Thioalkaloids via Copper-Catalyzed Thiolane Assembly. J Am Chem Soc 2017; 139:13272-13275. [PMID: 28911224 PMCID: PMC6309176 DOI: 10.1021/jacs.7b07685] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
An asymmetric total synthesis of (+)-6-hydroxythiobinupharidine (1b) and (-)-6-hydroxythionuphlutine (2b), a set of hemiaminal containing dimeric sesquiterpenes isolated from yellow water lilies of the Nuphar genus, is described. The central bis-spirocyclic tetrahydrothiophene ring was forged through the Stevens rearrangement of a sulfonium ylide, generated in situ from the coupling of a copper-carbene with a spirocyclic thietane. This strategy diverges both from the proposed biosynthesis1 and previous syntheses of this family of alkaloids,2,3 all of which employ dimerization of symmetric monomers to form the aforementioned thiaspirane. The coupling of unsymmetrical monomers allowed access to the unsymmetrically oxidized product 2b for the first time.
Collapse
Affiliation(s)
- Jacob J. Lacharity
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | | | | | - Artur K. Mailyan
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | | | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
29
|
Cano R, Zakarian A, McGlacken GP. Direct Asymmetric Alkylation of Ketones: Still Unconquered. Angew Chem Int Ed Engl 2017; 56:9278-9290. [PMID: 28497890 DOI: 10.1002/anie.201703079] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 04/27/2017] [Indexed: 01/07/2023]
Abstract
The alkylation of ketones is taught at basic undergraduate level. In many cases this transformation leads to the formation of a new stereogenic center. However, the apparent simplicity of the transformation is belied by a number of problems. So much so, that a general method for the direct asymmetric alkylation of ketones remains an unmet target. Despite the advancement of organocatalysis and transition-metal catalysis, neither field has provided an adequate solution. Indeed, even use of an efficient and general stoichiometric chiral reagent has yet to be reported. Herein we describe the state-of-the-art in terms of direct alkylation reactions of some carbonyl groups. We outline the limited progress that has been made with ketones, and potential routes towards ultimately achieving a widely applicable methodology for the asymmetric alkylation of ketones.
Collapse
Affiliation(s)
- Rafael Cano
- Department of Chemistry, University College Cork, Cork, Ireland.,Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Gerard P McGlacken
- Department of Chemistry, University College Cork, Cork, Ireland.,Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| |
Collapse
|
30
|
Affiliation(s)
- Rafael Cano
- Department of Chemistry; University College Cork; Cork Irland
- Analytical and Biological Chemistry Research Facility; University College Cork; Cork Irland
| | - Armen Zakarian
- Department of Chemistry and Biochemistry; University of California; Santa Barbara CA 93106 USA
| | - Gerard P. McGlacken
- Department of Chemistry; University College Cork; Cork Irland
- Analytical and Biological Chemistry Research Facility; University College Cork; Cork Irland
| |
Collapse
|
31
|
Martinez JA, Xiao Q, Zakarian A, Miller BG. Antidiabetic Disruptors of the Glucokinase-Glucokinase Regulatory Protein Complex Reorganize a Coulombic Interface. Biochemistry 2017; 56:3150-3157. [PMID: 28516783 DOI: 10.1021/acs.biochem.7b00377] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The glucokinase regulatory protein (GKRP) plays an essential role in glucose homeostasis by acting as a competitive inhibitor of glucokinase (GCK) and triggering its localization to the hepatocyte nucleus upon glucose deprivation. Metabolites such as fructose 6-phosphate and sorbitol 6-phosphate promote assembly of the GCK-GKRP complex, whereas fructose 1-phosphate and functionalized piperazines with potent in vivo antidiabetic activity disrupt the complex. Here, we establish the molecular basis by which these natural and synthetic ligands modulate the GCK-GKRP interaction. We demonstrate that a small-molecule disruptor of the protein-protein interaction utilizes a two-step conformational selection mechanism to associate with a rare GKRP conformation constituting 3% of the total population. Conformational heterogeneity of GKRP is localized to the N-terminus and deleting this region eliminates the ability of sorbitol 6-phosphate to promote the GCK-GKRP interaction. Stabilizing ligands favor an extended N-terminus, which sterically positions two arginine residues for optimal Coulombic interaction with a pair of carboxylate side chains from GCK. Conversely, disruptors promote a more compact N-terminus in which an interfacial arginine residue is stabilized in an unproductive orientation through a cation-π interaction with tyrosine 75. Eliminating the ability to sample this binding impaired conformation enhances the intrinsic inhibitory activity of GKRP. Elucidating the molecular basis of ligand-mediated control over the GCK-GKRP interaction is expected to impact the development and future refinement of therapeutic agents for diabetes and cardiovascular disease, which result from improper GKRP regulation of GCK.
Collapse
Affiliation(s)
- Juliana A Martinez
- Department of Chemistry and Biochemistry, Florida State University , Tallahassee, Florida 32303, United States
| | - Qing Xiao
- Department of Chemistry and Biochemistry, University of California, Santa Barbara , Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara , Santa Barbara, California 93106, United States
| | - Brian G Miller
- Department of Chemistry and Biochemistry, Florida State University , Tallahassee, Florida 32303, United States
| |
Collapse
|
32
|
Burns AS, Wagner AJ, Fulton JL, Young K, Zakarian A, Rychnovsky SD. Determination of the Absolute Configuration of β-Chiral Primary Alcohols Using the Competing Enantioselective Conversion Method. Org Lett 2017; 19:2953-2956. [PMID: 28508638 DOI: 10.1021/acs.orglett.7b01189] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A method for determining the absolute configuration of β-chiral primary alcohols has been developed. Enantioenriched alcohols were acylated in the presence of either enantiomer of the enantioselective acylation catalyst HBTM, and the faster reaction was determined by measuring product conversion using 1H NMR spectroscopic analysis. An empirical mnemonic was developed that correlates the absolute configuration of the alcohol to the faster reacting catalyst. Successful substrates for this method include primary alcohols that bear a "directing group" on the stereogenic center; directing groups include arenes, heteroarenes, enones, and halides.
Collapse
Affiliation(s)
- Alexander S Burns
- Department of Chemistry, University of California at Irvine , 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Alexander J Wagner
- Department of Chemistry, University of California at Irvine , 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Jennifer L Fulton
- Department of Chemistry, University of California at Irvine , 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Kyle Young
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Scott D Rychnovsky
- Department of Chemistry, University of California at Irvine , 1102 Natural Sciences II, Irvine, California 92697, United States
| |
Collapse
|
33
|
Molgó J, Marchot P, Aráoz R, Benoit E, Iorga BI, Zakarian A, Taylor P, Bourne Y, Servent D. Cyclic imine toxins from dinoflagellates: a growing family of potent antagonists of the nicotinic acetylcholine receptors. J Neurochem 2017; 142 Suppl 2:41-51. [PMID: 28326551 DOI: 10.1111/jnc.13995] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/13/2017] [Accepted: 02/15/2017] [Indexed: 12/24/2022]
Abstract
We present an overview of the toxicological profile of the fast-acting, lipophilic macrocyclic imine toxins, an emerging family of organic compounds associated with algal blooms, shellfish contamination and neurotoxicity. Worldwide, shellfish contamination incidents are expanding; therefore, the significance of these toxins for the shellfish food industry deserves further study. Emphasis is directed to the dinoflagellate species involved in their production, their chemical structures, and their specific mode of interaction with their principal natural molecular targets, the nicotinic acetylcholine receptors, or with the soluble acetylcholine-binding protein, used as a surrogate receptor model. The dinoflagellates Karenia selliformis and Alexandrium ostenfeldii / A. peruvianum have been implicated in the biosynthesis of gymnodimines and spirolides, while Vulcanodinium rugosum is the producer of pinnatoxins and portimine. The cyclic imine toxins are characterized by a macrocyclic skeleton comprising 14-27 carbon atoms, flanked by two conserved moieties, the cyclic imine and the spiroketal ring system. These phycotoxins generally display high affinity and broad specificity for the muscle type and neuronal nicotinic acetylcholine receptors, a feature consistent with their binding site at the receptor subunit interfaces, composed of residues highly conserved among all nAChRs, and explaining the diverse toxicity among animal species. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.
Collapse
Affiliation(s)
- Jordi Molgó
- Commissariat à l'Energie Atomique et aux énergies alternatives (CEA), Institut de Biologie et Technologies de Saclay (IBITECS), Université Paris-Saclay, Service d'Ingénierie Moléculaire des Protéines, Gif-sur-Yvette, France.,Institut des Neurosciences Paris-Saclay, UMR 9197, Centre National de la Recherche Scientifique (CNRS)/Université Paris-Sud, Gif-sur-Yvette Cedex, France
| | - Pascale Marchot
- Aix-Marseille Université / Centre National de la Recherche Scientifique, Architecture et Fonction des Macromolécules Biologiques laboratory, Marseille, France
| | - Rómulo Aráoz
- Commissariat à l'Energie Atomique et aux énergies alternatives (CEA), Institut de Biologie et Technologies de Saclay (IBITECS), Université Paris-Saclay, Service d'Ingénierie Moléculaire des Protéines, Gif-sur-Yvette, France.,Institut des Neurosciences Paris-Saclay, UMR 9197, Centre National de la Recherche Scientifique (CNRS)/Université Paris-Sud, Gif-sur-Yvette Cedex, France
| | - Evelyne Benoit
- Commissariat à l'Energie Atomique et aux énergies alternatives (CEA), Institut de Biologie et Technologies de Saclay (IBITECS), Université Paris-Saclay, Service d'Ingénierie Moléculaire des Protéines, Gif-sur-Yvette, France.,Institut des Neurosciences Paris-Saclay, UMR 9197, Centre National de la Recherche Scientifique (CNRS)/Université Paris-Sud, Gif-sur-Yvette Cedex, France
| | - Bogdan I Iorga
- Centre National de la Recherche Scientifique (CNRS), Institut de Chimie des Substances Naturelles, UPR 2301, Labex LERMIT, Gif-sur-Yvette, France
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, California, USA
| | - Palmer Taylor
- Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California, USA
| | - Yves Bourne
- Aix-Marseille Université / Centre National de la Recherche Scientifique, Architecture et Fonction des Macromolécules Biologiques laboratory, Marseille, France
| | - Denis Servent
- Commissariat à l'Energie Atomique et aux énergies alternatives (CEA), Institut de Biologie et Technologies de Saclay (IBITECS), Université Paris-Saclay, Service d'Ingénierie Moléculaire des Protéines, Gif-sur-Yvette, France
| |
Collapse
|
34
|
Yu K, Lu P, Jackson JJ, Nguyen TAD, Alvarado J, Stivala CE, Ma Y, Mack KA, Hayton TW, Collum DB, Zakarian A. Lithium Enolates in the Enantioselective Construction of Tetrasubstituted Carbon Centers with Chiral Lithium Amides as Noncovalent Stereodirecting Auxiliaries. J Am Chem Soc 2017; 139:527-533. [PMID: 27997174 PMCID: PMC6097510 DOI: 10.1021/jacs.6b11673] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lithium enolates derived from carboxylic acids are ubiquitous intermediates in organic synthesis. Asymmetric transformations with these intermediates, a central goal of organic synthesis, are typically carried out with covalently attached chiral auxiliaries. An alternative approach is to utilize chiral reagents that form discrete, well-defined aggregates with lithium enolates, providing a chiral environment conducive of asymmetric bond formation. These reagents effectively act as noncovalent, or traceless, chiral auxiliaries. Lithium amides are an obvious choice for such reagents as they are known to form mixed aggregates with lithium enolates. We demonstrate here that mixed aggregates can effect highly enantioselective transformations of lithium enolates in several classes of reactions, most notably in transformations forming tetrasubstituted and quaternary carbon centers. Easy recovery of the chiral reagent by aqueous extraction is another practical advantage of this one-step protocol. Crystallographic, spectroscopic, and computational studies of the central reactive aggregate, which provide insight into the origins of selectivity, are also reported.
Collapse
Affiliation(s)
- Kai Yu
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Ping Lu
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Jeffrey J Jackson
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Thuy-Ai D Nguyen
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Joseph Alvarado
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Craig E Stivala
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Yun Ma
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States
| | - Kyle A Mack
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States
| | - Trevor W Hayton
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - David B Collum
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| |
Collapse
|
35
|
Abstract
A method for a directed stereoselective guanidinylation of alkenes is described. The guanidine unit can be delivered as an intact fragment by a hydroxy or carboxy group, usually with a high level of stereocontrol. After the guanidine delivery, the directing group can be cleaved under exceptionally mild conditions, typically by alcoholysis in the presence of acetic acid. Broad functional group tolerance and mild reaction conditions for the cycloguanidilation suggest applications in medicinal chemistry and natural products synthesis.
Collapse
Affiliation(s)
- Artur K. Mailyan
- Department of Chemistry and Biochemsitry, University of California, Santa Barbara, California 93110, United States
| | - Kyle Young
- Department of Chemistry and Biochemsitry, University of California, Santa Barbara, California 93110, United States
| | - Joanna L. Chen
- Department of Chemistry and Biochemsitry, University of California, Santa Barbara, California 93110, United States
| | - Bradley T. Reid
- Department of Chemistry and Biochemsitry, University of California, Santa Barbara, California 93110, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemsitry, University of California, Santa Barbara, California 93110, United States
| |
Collapse
|
36
|
Alvarado J, Fournier J, Zakarian A. Synthesis of Functionalized Dihydrobenzofurans by Direct Aryl C-O Bond Formation under Mild Conditions. Angew Chem Int Ed Engl 2016; 55:11625-11628. [PMID: 27534735 PMCID: PMC5189712 DOI: 10.1002/anie.201605648] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 07/23/2016] [Indexed: 02/01/2023]
Abstract
A method for the synthesis of dihydrobenzofurans by a direct aryl C-O bond formation is described. A mechanistic pathway for the reaction, distinct from previously described similar transformations, allows for mild reaction conditions that are expected to be compatible with functionalized substrates.
Collapse
Affiliation(s)
- Joseph Alvarado
- Department of Chemistry and Biochemistry University of California, Santa Barbara CA 93106 (USA)
| | - Jeremy Fournier
- Department of Chemistry and Biochemistry University of California, Santa Barbara CA 93106 (USA)
| | - Armen Zakarian
- Department of Chemistry and Biochemistry University of California, Santa Barbara CA 93106 (USA)
| |
Collapse
|
37
|
Alvarado J, Fournier J, Zakarian A. Synthesis of Functionalized Dihydrobenzofurans by Direct Aryl C−O Bond Formation under Mild Conditions. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605648] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Joseph Alvarado
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106 USA
| | - Jeremy Fournier
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106 USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106 USA
| |
Collapse
|
38
|
Ma Y, Mack KA, Liang J, Keresztes I, Collum DB, Zakarian A. Mixed Aggregates of the Dilithiated Koga Tetraamine: NMR Spectroscopic and Computational Studies. Angew Chem Int Ed Engl 2016; 55:10093-7. [PMID: 27435147 DOI: 10.1002/anie.201605199] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Indexed: 01/11/2023]
Abstract
A combination of (1) H, (6) Li, (13) C, and (15) N NMR spectroscopies and density functional theory computations explores the formation of mixed aggregates by a dilithium salt of a C2 -symmetric chiral tetraamine (Koga's base). Lithium halides, acetylides, alkoxides, and monoalkylamides form isostructural trilithiated mixed aggregates with few exceptions. (6) Li-(13) C and (6) Li-(15) N couplings reveal heretofore undetected transannular contacts (laddering) with lithium acetylides and lithium monoalkylamides. Marked temperature-dependent (15) N chemical shifts seem to be associated with this laddering. Computational studies shed light on the general structures of the aggregates, their penchant for laddering, and the stereochemical consequences of aggregation.
Collapse
Affiliation(s)
- Yun Ma
- Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853-1301, USA
| | - Kyle A Mack
- Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853-1301, USA
| | - Jun Liang
- Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853-1301, USA
| | - Ivan Keresztes
- Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853-1301, USA
| | - David B Collum
- Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853-1301, USA.
| | - Armen Zakarian
- Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA, 93106, USA.
| |
Collapse
|
39
|
Ma Y, Mack KA, Liang J, Keresztes I, Collum DB, Zakarian A. Mixed Aggregates of the Dilithiated Koga Tetraamine: NMR Spectroscopic and Computational Studies. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605199] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Yun Ma
- Chemistry and Chemical Biology; Cornell University; Ithaca NY 14853-1301 USA
| | - Kyle A. Mack
- Chemistry and Chemical Biology; Cornell University; Ithaca NY 14853-1301 USA
| | - Jun Liang
- Chemistry and Chemical Biology; Cornell University; Ithaca NY 14853-1301 USA
| | - Ivan Keresztes
- Chemistry and Chemical Biology; Cornell University; Ithaca NY 14853-1301 USA
| | - David B. Collum
- Chemistry and Chemical Biology; Cornell University; Ithaca NY 14853-1301 USA
| | - Armen Zakarian
- Chemistry and Biochemistry; University of California, Santa Barbara; Santa Barbara CA 93106 USA
| |
Collapse
|
40
|
Mailyan AK, Eickhoff JA, Minakova AS, Gu Z, Lu P, Zakarian A. Cutting-Edge and Time-Honored Strategies for Stereoselective Construction of C–N Bonds in Total Synthesis. Chem Rev 2016; 116:4441-557. [DOI: 10.1021/acs.chemrev.5b00712] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Artur K. Mailyan
- Department
of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - John A. Eickhoff
- Department
of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Anastasiia S. Minakova
- Department
of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Zhenhua Gu
- Department
of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Ping Lu
- Department
of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department
of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
41
|
Aráoz R, Hess P, Pelissier F, Benoit E, Servent D, Zakarian A, Molgó J. Cyclic imine toxins: From shellfish poisoning to neuroscience: The case of acyl derivatives. Biochem Pharmacol 2015. [DOI: 10.1016/j.bcp.2015.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
42
|
Kobayashi H, Eickhoff JA, Zakarian A. Synthesis of 2-Aminoazoles from Thioesters via α-Heterosubstituted Ketones by Copper-Mediated Cross-Coupling. J Org Chem 2015; 80:9989-99. [PMID: 26378626 DOI: 10.1021/acs.joc.5b01558] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Facile synthesis of a variety of α-heterosubstituted ketones under mild conditions was achieved by copper-mediated cross-coupling of thioesters with functionalized organostannanes. Application of this coupling methodology provided a concise pathway for the conversion of carboxylic acids to 2-aminoimidazoles, 2-aminothiazoles, and 2-aminooxazoles via thioesters in practical yields.
Collapse
Affiliation(s)
- Hiroyuki Kobayashi
- Daiichi Sankyo Co., Ltd. , 1-2-58 Hiromachi, Shinagawa-ku, Tokyo 140-8710, Japan.,Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - John A Eickhoff
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| |
Collapse
|
43
|
Stivala CE, Benoit E, Aráoz R, Servent D, Novikov A, Molgó J, Zakarian A. Synthesis and biology of cyclic imine toxins, an emerging class of potent, globally distributed marine toxins. Nat Prod Rep 2015; 32:411-35. [PMID: 25338021 DOI: 10.1039/c4np00089g] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
From a small group of exotic compounds isolated only two decades ago, Cyclic Imine (CI) toxins have become a major class of marine toxins with global distribution. Their distinct chemical structure, biological mechanism of action, and intricate chemistry ensures that CI toxins will continue to be the subject of fascinating fundamental studies in the broad fields of chemistry, chemical biology, and toxicology. The worldwide occurrence of potent CI toxins in marine environments, their accumulation in shellfish, and chemical stability are important considerations in assessing risk factors for human health. This review article aims to provide an account of chemistry, biology, and toxicology of CI toxins from their discovery to the present day.
Collapse
Affiliation(s)
- Craig E Stivala
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | | | | | | | | | | | | |
Collapse
|
44
|
Lu P, Herrmann AT, Zakarian A. Toward the Synthesis of Nuphar Sesquiterpene Thioalkaloids: Stereodivergent Rhodium-Catalyzed Synthesis of the Thiolane Subunit. J Org Chem 2015; 80:7581-9. [PMID: 26147579 DOI: 10.1021/acs.joc.5b01177] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A stereodivergent approach to the central thiolane subunit of Nuphar sesquiterpene thioalkaloids has been developed. This approach features a rhodium-catalyzed Stevens-type rearrangement in conjunction with an enzyme resolution reaction. Further elaboration into a polycyclic ring system via alcohol oxidation and ring-closing metathesis is also described.
Collapse
Affiliation(s)
- Ping Lu
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Aaron T Herrmann
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
45
|
Jackson JJ, Kobayashi H, Steffens SD, Zakarian A. 10-Step Asymmetric Total Synthesis and Stereochemical Elucidation of (+)-Dragmacidin D. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201504113] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
46
|
Jackson JJ, Kobayashi H, Steffens SD, Zakarian A. 10-Step Asymmetric Total Synthesis and Stereochemical Elucidation of (+)-Dragmacidin D. Angew Chem Int Ed Engl 2015; 54:9971-5. [PMID: 26130270 DOI: 10.1002/anie.201504113] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Indexed: 12/22/2022]
Abstract
The asymmetric synthesis of dragmacidin D (1) was completed in 10 steps. Its sole stereocenter was set by using direct asymmetric alkylation enabled by a C2-symmetric tetramine and lithium N-(trimethylsilyl)-tert-butylamide as the enolization reagent. A central Larock indole synthesis was employed in a convergent assembly of the heterocyclic subunits. The stereochemical evidence from this work strongly supports the predicted S configuration at the 6''' position, which is consistent with other members of the dragmacidin family of natural products.
Collapse
Affiliation(s)
- Jeffrey J Jackson
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 (USA)
| | - Hiroyuki Kobayashi
- Daiichi Sankyo Co., LTD, 1-2-58, Hiromachi, Shinagawa-ku, Tokyo 140-8710 (Japan)
| | - Sophia D Steffens
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 (USA)
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 (USA).
| |
Collapse
|
47
|
Bourne Y, Sulzenbacher G, Radić Z, Aráoz R, Reynaud M, Benoit E, Zakarian A, Servent D, Molgó J, Taylor P, Marchot P. Marine Macrocyclic Imines, Pinnatoxins A and G: Structural Determinants and Functional Properties to Distinguish Neuronal α7 from Muscle α1(2)βγδ nAChRs. Structure 2015; 23:1106-15. [PMID: 26004441 DOI: 10.1016/j.str.2015.04.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 04/03/2015] [Accepted: 04/04/2015] [Indexed: 10/23/2022]
Abstract
Pinnatoxins are macrocyclic imine phycotoxins associated with algal blooms and shellfish toxicity. Functional analysis of pinnatoxin A and pinnatoxin G by binding and voltage-clamp electrophysiology on membrane-embedded neuronal α7, α4β2, α3β2, and muscle-type α12βγδ nicotinic acetylcholine receptors (nAChRs) reveals high-affinity binding and potent antagonism for the α7 and α12βγδ subtypes. The toxins also bind to the nAChR surrogate, acetylcholine-binding protein (AChBP), with low Kd values reflecting slow dissociation. Crystal structures of pinnatoxin-AChBP complexes (1.9-2.2 Å resolution) show the multiple anchoring points of the hydrophobic portion, the cyclic imine, and the substituted bis-spiroketal and cyclohexene ring systems of the pinnatoxins that dictate tight binding between the opposing loops C and F at the receptor subunit interface, as observed for the 13-desmethyl-spirolide C and gymnodimine A congeners. Uniquely, however, the bulky bridged EF-ketal ring specific to the pinnatoxins extends radially from the interfacial-binding pocket to interact with the sequence-variable loop F and govern nAChR subtype selectivity and central neurotoxicity.
Collapse
Affiliation(s)
- Yves Bourne
- Aix-Marseille Université, Laboratoire Architecture et Fonction des Macromolécules Biologiques, Campus Luminy, 13288 Marseille cedex 9, France; Centre National de la Recherche Scientifique, Laboratoire Architecture et Fonction des Macromolécules Biologiques, Campus Luminy, 13288 Marseille cedex 9, France.
| | - Gerlind Sulzenbacher
- Aix-Marseille Université, Laboratoire Architecture et Fonction des Macromolécules Biologiques, Campus Luminy, 13288 Marseille cedex 9, France; Centre National de la Recherche Scientifique, Laboratoire Architecture et Fonction des Macromolécules Biologiques, Campus Luminy, 13288 Marseille cedex 9, France
| | - Zoran Radić
- Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093-0650, USA
| | - Rómulo Aráoz
- Institut des Neurosciences Paris-Saclay, Centre National de la Recherche Scientifique, 91190 Gif-sur-Yvette, France; Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette, France
| | - Morgane Reynaud
- Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette, France
| | - Evelyne Benoit
- Institut des Neurosciences Paris-Saclay, Centre National de la Recherche Scientifique, 91190 Gif-sur-Yvette, France; Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette, France
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California Santa Barbara, CA 93106-9510, USA
| | - Denis Servent
- Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette, France
| | - Jordi Molgó
- Institut des Neurosciences Paris-Saclay, Centre National de la Recherche Scientifique, 91190 Gif-sur-Yvette, France; Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette, France
| | - Palmer Taylor
- Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093-0650, USA
| | - Pascale Marchot
- Aix-Marseille Université, Laboratoire Architecture et Fonction des Macromolécules Biologiques, Campus Luminy, 13288 Marseille cedex 9, France; Centre National de la Recherche Scientifique, Laboratoire Architecture et Fonction des Macromolécules Biologiques, Campus Luminy, 13288 Marseille cedex 9, France.
| |
Collapse
|
48
|
Affiliation(s)
- Qing Xiao
- Department of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Kyle Young
- Department of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Armen Zakarian
- Department of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
49
|
Young K, Xiao Q, Zakarian A. Toward the Synthesis of Muironolide A: Synthesis and Structure of Heteroleptic Lanthanide-Terpyridine Complexes with 2-Oxo Amides. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500174] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
50
|
Lu P, Jackson JJ, Eickhoff JA, Zakarian A. Direct enantioselective conjugate addition of carboxylic acids with chiral lithium amides as traceless auxiliaries. J Am Chem Soc 2015; 137:656-9. [PMID: 25562717 PMCID: PMC4308744 DOI: 10.1021/ja512213c] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Michael addition is a premier synthetic method for carbon-carbon and carbon-heteroatom bond formation. Using chiral dilithium amides as traceless auxiliaries, we report the direct enantioselective Michael addition of carboxylic acids. A free carboxyl group in the product provides versatility for further functionalization, and the chiral reagent can be readily recovered by extraction with aqueous acid. The method has been applied in the enantioselective total synthesis of the purported structure of pulveraven B.
Collapse
Affiliation(s)
- Ping Lu
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | | | | | | |
Collapse
|