1
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Nicastri KA, Gerstner NC, Schomaker JM. Progress toward the Total Synthesis of Jogyamycin Using a Tandem Ichikawa/Winstein Rearrangement. Org Lett 2023; 25:8279-8283. [PMID: 37997640 PMCID: PMC10789149 DOI: 10.1021/acs.orglett.3c03286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
Jogyamycin is a densely functionalized aminocyclopentitol that displays potent antiprotozoal activity. Herein, we report a route toward this natural product that utilizes an unprecedented transformation involving a tandem Ichikawa-Winstein rearrangement to install the C-1/C-2 diamine core. Attempts to further functionalize the C-3/C-4 alkene en route to jogyamycin are also discussed.
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Affiliation(s)
- Kate A Nicastri
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Nels C Gerstner
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Jennifer M Schomaker
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States
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2
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Tsunoda T, Tanoeyadi S, Proteau PJ, Mahmud T. The chemistry and biology of natural ribomimetics and related compounds. RSC Chem Biol 2022; 3:519-538. [PMID: 35656477 PMCID: PMC9092360 DOI: 10.1039/d2cb00019a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 04/06/2022] [Indexed: 11/21/2022] Open
Abstract
Natural ribomimetics represent an important group of specialized metabolites with significant biological activities. Many of the activities, e.g., inhibition of seryl-tRNA synthetases, glycosidases, or ribosomes, are manifestations of their structural resemblance to ribose or related sugars, which play roles in the structural, physiological, and/or reproductive functions of living organisms. Recent studies on the biosynthesis and biological activities of some natural ribomimetics have expanded our understanding on how they are made in nature and why they have great potential as pharmaceutically relevant products. This review article highlights the discovery, biological activities, biosynthesis, and development of this intriguing class of natural products.
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Affiliation(s)
- Takeshi Tsunoda
- Department of Pharmaceutical Sciences, Oregon State University Corvallis OR 97331 USA
| | - Samuel Tanoeyadi
- Department of Pharmaceutical Sciences, Oregon State University Corvallis OR 97331 USA
| | - Philip J Proteau
- Department of Pharmaceutical Sciences, Oregon State University Corvallis OR 97331 USA
| | - Taifo Mahmud
- Department of Pharmaceutical Sciences, Oregon State University Corvallis OR 97331 USA
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3
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Gerstner NC, Nicastri KA, Schomaker JM. Strategien für die Synthese von Pactamycin und Jogyamycin. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202004560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Nels C. Gerstner
- Department of Chemistry University of Wisconsin 1101 University Avenue Madison WI 53706 USA
| | - Kate A. Nicastri
- Department of Chemistry University of Wisconsin 1101 University Avenue Madison WI 53706 USA
| | - Jennifer M. Schomaker
- Department of Chemistry University of Wisconsin 1101 University Avenue Madison WI 53706 USA
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4
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Gerstner NC, Nicastri KA, Schomaker JM. Strategies for the Syntheses of Pactamycin and Jogyamycin. Angew Chem Int Ed Engl 2021; 60:14252-14271. [PMID: 32392399 DOI: 10.1002/anie.202004560] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Indexed: 01/24/2023]
Abstract
Pactamycin and jogyamycin are aminocyclopentitol natural products, where each core carbon bears a stereodefined alcohol or amine moiety. Their structural complexity, coupled with the diversity of functional groups coexisting in a condensed space, make them fascinating synthetic targets in their own right. Pactamycin and its derivatives bind to the 30S ribosomal subunit and display activity against parasites responsible for drug-resistant malaria and African sleeping sickness; however, efforts to develop their therapeutic potential have been hampered by their cellular toxicity. Interestingly, bioengineered analogues display differences in selectivity and toxicity towards mammalian cells, spurring efforts to develop flexible strategies to thoroughly probe structure-activity relationships (SAR), particularly in analogues lacking the C7 hydroxyl group of pactamycin. This review compares and contrasts approaches towards pactamycin and jogyamycin, including two successful total syntheses of the former. The implications of each route for preparing analogues to inform SAR and lead to compounds with increased selectivity for binding malarial over human ribosomes are briefly discussed.
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Affiliation(s)
- Nels C Gerstner
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI, 53706, USA
| | - Kate A Nicastri
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI, 53706, USA
| | - Jennifer M Schomaker
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI, 53706, USA
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5
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Gerstner NC, Schomaker JM. Stereocontrolled Synthesis of the Aminocyclopentitol Core of Jogyamycin via an Ichikawa Rearrangement Reaction. J Org Chem 2019; 84:14092-14100. [PMID: 31578059 DOI: 10.1021/acs.joc.9b02249] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Jogyamycin is a member of the aminocyclopentitol class of natural products that exhibits significant antiprotozoal activities against diseases that include African sleeping sickness and malaria. Herein, we report a route to the core of this natural product via an underutilized Ichikawa rearrangement as a key step. This route efficiently forms the cyclopentane ring from simple and easily accessible starting materials and rapidly installs the C1/C4/C5 polar functional groups. In addition, this strategy shows excellent potential for the preparation of analogues of jogyamycin to study how structural changes impact the selectivity in binding to the ribosome.
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Affiliation(s)
- Nels C Gerstner
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Jennifer M Schomaker
- Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , Wisconsin 53706 , United States
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6
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Kudo F, Zhang J, Sato S, Hirayama A, Eguchi T. Functional Characterization of 3-Aminobenzoic Acid Adenylation Enzyme PctU and UDP-N-Acetyl-d-Glucosamine: 3-Aminobenzoyl-ACP Glycosyltransferase PctL in Pactamycin Biosynthesis. Chembiochem 2019; 20:2458-2462. [PMID: 31059166 DOI: 10.1002/cbic.201900239] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Indexed: 12/27/2022]
Abstract
Pactamycin is an antibiotic produced by Streptomyces pactum with antitumor and antimalarial properties. Pactamycin has a unique aminocyclitol core that is decorated with 3-aminoacetophenone, 6-methylsaliciate, and an N,N-dimethylcarbamoyl group. Herein, we show that the adenylation enzyme PctU activates 3-aminobenzoic acid (3ABA) with adenosine triphosphate and ligates it to the holo form of the discrete acyl carrier protein PctK to yield 3ABA-PctK. Then, 3ABA-PctK is N-glycosylated with uridine diphosphate-N-acetyl-d-glucosamine (UDP-GlcNAc) by the glycosyltransferase PctL to yield GlcNAc-3ABA-PctK. Because 3ABA is known to be a precursor of the 3-aminoacetophenone moiety, PctU appears to be a gatekeeper that selects the appropriate 3-aminobenzoate starter unit. Overall, we propose that acyl carrier protein-bound glycosylated 3ABA derivatives are biosynthetic intermediates of pactamycin biosynthesis.
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Affiliation(s)
- Fumitaka Kudo
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Jiahao Zhang
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Shusuke Sato
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Akane Hirayama
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Tadashi Eguchi
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo, 152-8551, Japan
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7
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Kim T, Matsushita S, Matsudaira S, Doi T, Hirota S, Park YT, Igarashi M, Hatano M, Ikeda N, Ham J, Nakata M, Saikawa Y. Total Synthesis of Pactalactam, an Imidazolidinone-Type Pactamycin Analogue. Org Lett 2019; 21:3554-3557. [PMID: 31058517 DOI: 10.1021/acs.orglett.9b00905] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first total synthesis of pactalactam was accomplished using substrate-controlled stereoselective aziridination and regioselective aziridine ring-opening to construct three continuous amino groups on an octasubstituted cyclopentane core. The cyclopentane framework was obtained by ring-closing metathesis and aldol coupling using a l-threonine-derived oxazoline compound. Cyclic urea formation, m-acetylphenyl group introduction by Chan-Lam coupling, and primary alcohol-selective acylation yielded the reported pactalactam structure. The presence of pactalactam in the fermentation broth of pactamycin-producing bacteria was also confirmed.
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Affiliation(s)
- Taejung Kim
- Department of Applied Chemistry, Faculty of Science and Technology , Keio University , 3-14-1 Hiyoshi , Kohoku-ku, Yokohama 223-8522 , Japan.,Natural Products Research Institute , Korea Institute of Science and Technology (KIST) , 679 Saimdang-ro , Gangneung 25451 , Republic of Korea
| | - Shohei Matsushita
- Department of Applied Chemistry, Faculty of Science and Technology , Keio University , 3-14-1 Hiyoshi , Kohoku-ku, Yokohama 223-8522 , Japan
| | - So Matsudaira
- Department of Applied Chemistry, Faculty of Science and Technology , Keio University , 3-14-1 Hiyoshi , Kohoku-ku, Yokohama 223-8522 , Japan
| | - Tsuyoshi Doi
- Department of Applied Chemistry, Faculty of Science and Technology , Keio University , 3-14-1 Hiyoshi , Kohoku-ku, Yokohama 223-8522 , Japan
| | - Shinji Hirota
- Department of Applied Chemistry, Faculty of Science and Technology , Keio University , 3-14-1 Hiyoshi , Kohoku-ku, Yokohama 223-8522 , Japan
| | - Young-Tae Park
- Natural Products Research Institute , Korea Institute of Science and Technology (KIST) , 679 Saimdang-ro , Gangneung 25451 , Republic of Korea
| | - Masayuki Igarashi
- Institute of Microbial Chemistry (BIKAKEN) , 3-14-23 Kamiosaki , Shinagawa-ku, Tokyo 141-0021 , Japan
| | - Masaki Hatano
- Institute of Microbial Chemistry (BIKAKEN) , 3-14-23 Kamiosaki , Shinagawa-ku, Tokyo 141-0021 , Japan
| | - Noriko Ikeda
- Institute of Microbial Chemistry (BIKAKEN) , 3-14-23 Kamiosaki , Shinagawa-ku, Tokyo 141-0021 , Japan
| | - Jungyeob Ham
- Natural Products Research Institute , Korea Institute of Science and Technology (KIST) , 679 Saimdang-ro , Gangneung 25451 , Republic of Korea
| | - Masaya Nakata
- Department of Applied Chemistry, Faculty of Science and Technology , Keio University , 3-14-1 Hiyoshi , Kohoku-ku, Yokohama 223-8522 , Japan
| | - Yoko Saikawa
- Department of Applied Chemistry, Faculty of Science and Technology , Keio University , 3-14-1 Hiyoshi , Kohoku-ku, Yokohama 223-8522 , Japan
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8
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Yñigez-Gutierrez AE, Bachmann BO. Fixing the Unfixable: The Art of Optimizing Natural Products for Human Medicine. J Med Chem 2019; 62:8412-8428. [PMID: 31026161 DOI: 10.1021/acs.jmedchem.9b00246] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Molecules isolated from natural sources including bacteria, fungi, and plants are a long-standing source of therapeutics that continue to add to our medicinal arsenal today. Despite their potency and prominence in the clinic, complex natural products often exhibit a number of liabilities that hinder their development as therapeutics, which may be partially responsible for the current trend away from natural product discovery, research, and development. However, advances in synthetic biology and organic synthesis have inspired a new generation of natural product chemists to tackle powerful undeveloped scaffolds. In this Perspective, we will present case studies demonstrating the historical and current focus on making targeted, but significant, changes to natural product scaffolds via biosynthetic gene cluster manipulation, total synthesis, semisynthesis, or a combination of these methods, with a focus on increasing activity, decreasing toxicity, or improving chemical and pharmacological properties.
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Affiliation(s)
| | - Brian O Bachmann
- Department of Chemistry , Vanderbilt University , Nashville , Tennessee 37235 , United States
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9
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Eshon J, Gerstner NC, Schomaker JM. Oxidative allene amination for the synthesis of nitrogen-containing heterocycles. ARKIVOC 2018; 2018:204-233. [PMID: 31903453 PMCID: PMC6941799 DOI: 10.24820/ark.5550190.p010.670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The prevalence of stereochemically complex amines in natural products, pharmaceuticals and other bioactive compounds, coupled with the challenges inherent in their preparation, has inspired our work to develop new and versatile methodologies for the synthesis of amine-containing stereotriads ('triads'). The key step is a highly chemo-, regio-, and stereoselective transition-metal catalyzed nitrene transfer reaction that transforms one of the cumulated double bonds of an allene precursor into a bicyclic methyleneaziridine intermediate. This account summarizes our strategies to rapidly elaborate such intermediates into stereochemically rich, densely functionalized amine triads, nitrogen heterocycles, aminated carbocycles and other useful synthetic building blocks.
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Affiliation(s)
- Josephine Eshon
- Department of Chemistry, 1101 University Avenue, Madison, WI 53706, U.S.A
| | - Nels C Gerstner
- Department of Chemistry, 1101 University Avenue, Madison, WI 53706, U.S.A
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10
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Trost BM, Zhang L, Lam TM. Synthesis of the Aminocyclitol Core of Jogyamycin via an Enantioselective Pd-Catalyzed Trimethylenemethane (TMM) Cycloaddition. Org Lett 2018; 20:3938-3942. [PMID: 29939033 DOI: 10.1021/acs.orglett.8b01518] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The use of β-nitroenamines as a new class of acceptors in the enantioselective Pd-catalyzed trimethylenemethane cycloaddition afforded differentiated 1,2-dinitrogen bearing cyclopentanes with three contiguous stereocenters. The utility of these acceptors was demonstrated with the efficient construction of the core of jogyamycin and aminocyclopentitols. Further elaboration of the cycloadducts provided a concise synthetic approach toward joygamycin.
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Affiliation(s)
- Barry M Trost
- Department of Chemistry , Stanford University , Stanford , California 94305-5580 , United States
| | - Lei Zhang
- Department of Chemistry , Stanford University , Stanford , California 94305-5580 , United States
| | - Tom M Lam
- Department of Chemistry , Stanford University , Stanford , California 94305-5580 , United States
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11
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Su JY, Olson DE, Ting SI, Du Bois J. Synthetic Studies Toward Pactamycin Highlighting Oxidative C-H and Alkene Amination Technologies. J Org Chem 2018; 83:7121-7134. [PMID: 29708344 DOI: 10.1021/acs.joc.8b00142] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A strategy enabled by C-H and alkene amination technologies for synthesizing the aminocyclitol natural product, pactamycin, is disclosed. This work features two disparate approaches for assembling the five-membered ring core of the target, the first of which utilizes acyl anion catalysis and a second involving β-ketoester aerobic hydroxylation. Installation of the C3-N bond, one of three contiguous nitrogen centers, is made possible through Rh-catalyzed allylic C-H amination of a sulfamate ester. Subsequent efforts are presented to introduce the C1,C2 cis-diamino moiety en route to pactamycin, including carbamate-mediated alkene aziridination. In the course of these studies, assembly of the core of C2- epi-pactamycate, which bears the carbon skeleton and all of the requisite nitrogen and oxygen functional groups found in the natural product, has been achieved.
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Affiliation(s)
- Justin Y Su
- Department of Chemistry , Stanford University , 337 Campus Drive , Stanford , California 94305 , United States
| | - David E Olson
- Department of Chemistry , Stanford University , 337 Campus Drive , Stanford , California 94305 , United States
| | - Stephen I Ting
- Department of Chemistry , Stanford University , 337 Campus Drive , Stanford , California 94305 , United States
| | - J Du Bois
- Department of Chemistry , Stanford University , 337 Campus Drive , Stanford , California 94305 , United States
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12
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Brumsted CJ, Carpenter EL, Indra AK, Mahmud T. Asymmetric Synthesis and Biological Activities of Pactamycin-Inspired Aminocyclopentitols. Org Lett 2018; 20:397-400. [DOI: 10.1021/acs.orglett.7b03681] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Corey J. Brumsted
- Department
of Chemistry and ‡Department of Pharmaceutical Sciences, Oregon State University, Corvallis, Oregon 97333, United States
| | | | | | - Taifo Mahmud
- Department
of Chemistry and ‡Department of Pharmaceutical Sciences, Oregon State University, Corvallis, Oregon 97333, United States
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13
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Rodrigues R, Lazib Y, Maury J, Neuville L, Leboeuf D, Dauban P, Darses B. Approach to pactamycin analogues using rhodium(ii)-catalyzed alkene aziridination and C(sp3)–H amination reactions. Org Chem Front 2018. [DOI: 10.1039/c7qo00878c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Application of dirhodium(ii)-catalyzed nitrene transfers allows for the preparation of a platform bearing the triamino moiety present in pactamycin.
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Affiliation(s)
- Romain Rodrigues
- Institut de Chimie des Substances Naturelles
- CNRS UPR 2301
- Univ. Paris-Sud
- Université Paris-Saclay
- 91198 Gif-sur-Yvette
| | - Yanis Lazib
- Institut de Chimie des Substances Naturelles
- CNRS UPR 2301
- Univ. Paris-Sud
- Université Paris-Saclay
- 91198 Gif-sur-Yvette
| | - Julien Maury
- Institut de Chimie des Substances Naturelles
- CNRS UPR 2301
- Univ. Paris-Sud
- Université Paris-Saclay
- 91198 Gif-sur-Yvette
| | - Luc Neuville
- Institut de Chimie des Substances Naturelles
- CNRS UPR 2301
- Univ. Paris-Sud
- Université Paris-Saclay
- 91198 Gif-sur-Yvette
| | - David Leboeuf
- Institut de Chimie Moléculaire et des Matériaux d'Orsay
- CNRS UMR 8182
- Univ. Paris-Sud
- Université Paris-Saclay
- 91405 Orsay cedex
| | - Philippe Dauban
- Institut de Chimie des Substances Naturelles
- CNRS UPR 2301
- Univ. Paris-Sud
- Université Paris-Saclay
- 91198 Gif-sur-Yvette
| | - Benjamin Darses
- Institut de Chimie des Substances Naturelles
- CNRS UPR 2301
- Univ. Paris-Sud
- Université Paris-Saclay
- 91198 Gif-sur-Yvette
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14
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Horwitz MA, Johnson JS. Local Desymmetrization through Diastereotopic Group Selection: An Enabling Strategy for Natural Product Synthesis. European J Org Chem 2017; 2017:1381-1390. [PMID: 28533701 PMCID: PMC5437555 DOI: 10.1002/ejoc.201601481] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Indexed: 12/22/2022]
Abstract
The application of desymmetrization strategies in chemical synthesis has allowed fundamentally new synthetic sequences that efficiently create dense and polyfunctional stereochemical arrays. Enantiotopic group discrimination has become a well-established method of global desymmetrization, while the conceptually unique strategy of local desymmetrization by diastereotopic group discrimination has its own advantages. This microreview focuses on the application of local desymmetrization in natural product synthesis and places a particular emphasis on the efficiency engendered by diastereotopic group discrimination. Local desymmetrization is subdivided into three distinct manifolds; examples under each paradigm are presented and compared.
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Affiliation(s)
- Matthew A Horwitz
- Department of Chemistry, The University of North Carolina at Chapel Hill Chapel Hill, NC 27599 (USA)
| | - Jeffrey S Johnson
- Department of Chemistry, The University of North Carolina at Chapel Hill Chapel Hill, NC 27599 (USA)
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15
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Gerstner NC, Adams CS, Grigg RD, Tretbar M, Rigoli JW, Schomaker JM. Diastereoselective Synthesis of the Aminocyclitol Core of Jogyamycin via an Allene Aziridination Strategy. Org Lett 2016; 18:284-7. [PMID: 26741730 DOI: 10.1021/acs.orglett.5b03453] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oxidative allene amination provides rapid access to densely functionalized amine-containing stereotriads through highly reactive bicyclic methyleneaziridine intermediates. This strategy has been demonstrated as a viable approach for the construction of the densely functionalized aminocyclitol core of jogyamycin, a natural product with potent antiprotozoal activity. Importantly, the flexibility of oxidative allene amination will enable the syntheses of modified aminocyclitol analogues of the jogyamycin core.
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Affiliation(s)
- Nels C Gerstner
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706, United States
| | - Christopher S Adams
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706, United States
| | - R David Grigg
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706, United States
| | - Maik Tretbar
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706, United States
| | - Jared W Rigoli
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706, United States
| | - Jennifer M Schomaker
- Department of Chemistry, University of Wisconsin , Madison, Wisconsin 53706, United States
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16
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Abstract
An enantioselective synthesis of the indole diterpenoid natural product paspaline is disclosed. Critical to this approach was the implementation of stereoselective desymmetrization reactions to assemble key stereocenters of the molecule. The design and execution of these tactics are described in detail, and a thorough analysis of observed outcomes is presented, ultimately providing the title compound in high stereopurity. This synthesis provides a novel template for preparing key stereocenters in this family of molecules, and the reactions developed en route to paspaline present a series of new synthetic disconnections in preparing steroidal natural products.
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Affiliation(s)
- Robert J. Sharpe
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Jeffrey S. Johnson
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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