1
|
Steele TS, Burkhardt I, Moore ML, de Rond T, Bone HK, Barry K, Bunting VM, Grimwood J, Handley LH, Rajasekar S, Talag J, Michael TP, Moore BS. Biosynthesis of Haloterpenoids in Red Algae via Microbial-like Type I Terpene Synthases. ACS Chem Biol 2024; 19:185-192. [PMID: 38081799 PMCID: PMC10985283 DOI: 10.1021/acschembio.3c00627] [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: 01/23/2024]
Abstract
Red algae or seaweeds produce highly distinctive halogenated terpenoid compounds, including the pentabromochlorinated monoterpene halomon that was once heralded as a promising anticancer agent. The first dedicated step in the biosynthesis of these natural product molecules is expected to be catalyzed by terpene synthase (TS) enzymes. Recent work has demonstrated an emerging class of type I TSs in red algal terpene biosynthesis. However, only one such enzyme from a notoriously haloterpenoid-producing red alga (Laurencia pacifica) has been functionally characterized and the product structure is not related to halogenated terpenoids. Herein, we report 10 new type I TSs from the red algae Portieria hornemannii, Plocamium pacificum, L. pacifica, and Laurencia subopposita that produce a diversity of halogenated mono- and sesquiterpenes. We used a combination of genome sequencing, terpenoid metabolomics, in vitro biochemistry, and bioinformatics to establish red algal TSs in all four species, including those associated with the selective production of key halogenated terpene precursors myrcene, trans-β-ocimene, and germacrene D-4-ol. These results expand on a small but growing number of characterized red algal TSs and offer insight into the biosynthesis of iconic halogenated algal compounds that are not without precedence elsewhere in biology.
Collapse
Affiliation(s)
- Taylor S. Steele
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States; Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, United States
| | - Immo Burkhardt
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Malia L. Moore
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States; The Plant Molecular and Cellular Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - Tristan de Rond
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States; School of Chemical Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Hannah K. Bone
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Kerrie Barry
- Lawrence Berkeley National Laboratory, JGI-DOE Joint Genome Institute, Berkeley, California 94720, United States
| | - Victoria Mae Bunting
- Arizona Genomics Institute, University of Arizona, Tucson, Arizona 85721, United States
| | - Jane Grimwood
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806, United States
| | - Lori H. Handley
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806, United States
| | - Shanmugam Rajasekar
- Arizona Genomics Institute, University of Arizona, Tucson, Arizona 85721, United States
| | - Jayson Talag
- Arizona Genomics Institute, University of Arizona, Tucson, Arizona 85721, United States
| | - Todd P. Michael
- The Plant Molecular and Cellular Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - Bradley S. Moore
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States; Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California 92093, United States
| |
Collapse
|
2
|
Al Zubaydi S, Onuigbo IO, Truesdell BL, Sevov CS. Cobalt-Catalyzed Electroreductive Alkylation of Unactivated Alkyl Chlorides with Conjugated Olefins. Angew Chem Int Ed Engl 2024; 63:e202313830. [PMID: 37963333 DOI: 10.1002/anie.202313830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 11/10/2023] [Accepted: 11/14/2023] [Indexed: 11/16/2023]
Abstract
Reactions of unactivated alkyl chlorides under mild and sustainable conditions are rare compared to those of alkyl bromides or iodides. As a result, synthetic methods capable of modifying the vast chemical space of chloroalkane reagents, wastes, and materials are limited. We report the cobalt-catalyzed reductive addition of unactivated alkyl chlorides to conjugated alkenes. Co-catalyzed activation of alkyl chlorides is performed under electroreductive conditions, and the resulting reactions constitute formal alkyl-alkyl bond formation. In addition to developing an operationally simple methodology, detailed mechanistic studies provide insights into the elementary steps of a proposed catalytic cycle. In particular, we propose a switch in the mechanism of C-Cl bond activation from nucleophilic substitution to halogen atom abstraction, which is critical for efficiently generating alkyl radicals. These mechanistic insights were leveraged in designing ligands that enable couplings of primary, secondary, and tertiary alkyl chlorides.
Collapse
Affiliation(s)
- Samir Al Zubaydi
- Department of Chemistry and Biochemistry, The Ohio State University, 151 West Woodruff Avenue, Columbus, OH 43210, USA
| | - Immaculata O Onuigbo
- Department of Chemistry and Biochemistry, The Ohio State University, 151 West Woodruff Avenue, Columbus, OH 43210, USA
| | - Blaise L Truesdell
- Department of Chemistry and Biochemistry, The Ohio State University, 151 West Woodruff Avenue, Columbus, OH 43210, USA
| | - Christo S Sevov
- Department of Chemistry and Biochemistry, The Ohio State University, 151 West Woodruff Avenue, Columbus, OH 43210, USA
| |
Collapse
|
3
|
Vennelakanti V, Li GL, Kulik HJ. Why Nonheme Iron Halogenases Do Not Fluorinate C-H Bonds: A Computational Investigation. Inorg Chem 2023; 62:19758-19770. [PMID: 37972340 DOI: 10.1021/acs.inorgchem.3c03215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
Selective halogenation is necessary for a range of fine chemical applications, including the development of therapeutic drugs. While synthetic processes to achieve C-H halogenation require harsh conditions, enzymes such as nonheme iron halogenases carry out some types of C-H halogenation, i.e., chlorination or bromination, with ease, while others, i.e., fluorination, have never been observed in natural or engineered nonheme iron enzymes. Using density functional theory and correlated wave function theory, we investigate the differences in structural and energetic preferences of the smaller fluoride and the larger chloride or bromide intermediates throughout the catalytic cycle. Although we find that the energetics of rate-limiting hydrogen atom transfer are not strongly impacted by fluoride substitution, the higher barriers observed during the radical rebound reaction for fluoride relative to chloride and bromide contribute to the difficulty of C-H fluorination. We also investigate the possibility of isomerization playing a role in differences in reaction selectivity, and our calculations reveal crucial differences in terms of isomer energetics of the key ferryl intermediate between fluoride and chloride/bromide intermediates. While formation of monodentate isomers believed to be involved in selective catalysis is shown for chloride and bromide intermediates, we find that formation of the fluoride monodentate intermediate is not possible in our calculations, which lack additional stabilizing interactions with the greater protein environment. Furthermore, the shorter Fe-F bonds are found to increase isomerization reaction barriers, suggesting that incorporation of residues that form a halogen bond with F and elongate Fe-F bonds could make selective C-H fluorination possible in nonheme iron halogenases. Our work highlights the differences between the fluoride and chloride/bromide intermediates and suggests potential steps toward engineering nonheme iron halogenases to enable selective C-H fluorination.
Collapse
Affiliation(s)
- Vyshnavi Vennelakanti
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Grace L Li
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| |
Collapse
|
4
|
Wang S, Wang L, Li F, Bai F. DeepSA: a deep-learning driven predictor of compound synthesis accessibility. J Cheminform 2023; 15:103. [PMID: 37919805 PMCID: PMC10621138 DOI: 10.1186/s13321-023-00771-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 10/20/2023] [Indexed: 11/04/2023] Open
Abstract
With the continuous development of artificial intelligence technology, more and more computational models for generating new molecules are being developed. However, we are often confronted with the question of whether these compounds are easy or difficult to synthesize, which refers to synthetic accessibility of compounds. In this study, a deep learning based computational model called DeepSA, was proposed to predict the synthesis accessibility of compounds, which provides a useful tool to choose molecules. DeepSA is a chemical language model that was developed by training on a dataset of 3,593,053 molecules using various natural language processing (NLP) algorithms, offering advantages over state-of-the-art methods and having a much higher area under the receiver operating characteristic curve (AUROC), i.e., 89.6%, in discriminating those molecules that are difficult to synthesize. This helps users select less expensive molecules for synthesis, reducing the time and cost required for drug discovery and development. Interestingly, a comparison of DeepSA with a Graph Attention-based method shows that using SMILES alone can also efficiently visualize and extract compound's informative features. DeepSA is available online on the below web server ( https://bailab.siais.shanghaitech.edu.cn/services/deepsa/ ) of our group, and the code is available at https://github.com/Shihang-Wang-58/DeepSA .
Collapse
Affiliation(s)
- Shihang Wang
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China
| | - Lin Wang
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China
| | - Fenglei Li
- School of Information Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China
| | - Fang Bai
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China.
- School of Information Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China.
- Shanghai Clinical Research and Trial Center, Shanghai, 201210, China.
| |
Collapse
|
5
|
Zhang D, Pu M, Liu Z, Zhou Y, Yang Z, Liu X, Wu YD, Feng X. Enantioselective anti-Dihalogenation of Electron-Deficient Olefin: A Triplet Halo-Radical Pylon Intermediate. J Am Chem Soc 2023; 145:4808-4818. [PMID: 36795915 DOI: 10.1021/jacs.2c13810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The textbook alkene halogenation reaction establishes straightforward access to vicinal dihaloalkanes. However, a robust catalytic method for dihalogenizing electron-deficient olefins in an enantioselective manner is still under development, and its mechanism remains controversial. Herein, we disclose efficient regio-, anti-diastereo-, and enantioselective dibromination, bromochlorination, and dichlorination reactions of enones catalyzed by a chiral N,N'-dioxide/Yb(OTf)3 complex. With the combination of electrophilic halogen and halide salts as halogenating agents, an array of homo- and heterodihalogenated derivatives is achieved in moderate to good enantioselectivities. Moreover, DFT calculations reveal that a novel triplet halo-radical pylon intermediate is probable in accounting for the exclusive regio- and anti-diastereoselectivity.
Collapse
Affiliation(s)
- Dong Zhang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Maoping Pu
- Shenzhen Bay Laboratory, Shenzhen 518055, China
| | - Zhenzhong Liu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Yuqiao Zhou
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Zhendong Yang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Yun-Dong Wu
- Shenzhen Bay Laboratory, Shenzhen 518055, China.,Laboratory of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| |
Collapse
|
6
|
Gribble GW. Naturally Occurring Organohalogen Compounds-A Comprehensive Review. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2023; 121:1-546. [PMID: 37488466 DOI: 10.1007/978-3-031-26629-4_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
The present volume is the third in a trilogy that documents naturally occurring organohalogen compounds, bringing the total number-from fewer than 25 in 1968-to approximately 8000 compounds to date. Nearly all of these natural products contain chlorine or bromine, with a few containing iodine and, fewer still, fluorine. Produced by ubiquitous marine (algae, sponges, corals, bryozoa, nudibranchs, fungi, bacteria) and terrestrial organisms (plants, fungi, bacteria, insects, higher animals) and universal abiotic processes (volcanos, forest fires, geothermal events), organohalogens pervade the global ecosystem. Newly identified extraterrestrial sources are also documented. In addition to chemical structures, biological activity, biohalogenation, biodegradation, natural function, and future outlook are presented.
Collapse
Affiliation(s)
- Gordon W Gribble
- Department of Chemistry, Dartmouth College, Hanover, NH, 03755, USA.
| |
Collapse
|
7
|
Lubaev A, Rathnayake MD, Eze F, Bayeh-Romero L. Catalytic Chemo-, Regio-, Diastereo-, and Enantioselective Bromochlorination of Unsaturated Systems Enabled by Lewis Base-Controlled Chloride Release. J Am Chem Soc 2022; 144:13294-13301. [PMID: 35820071 PMCID: PMC9945878 DOI: 10.1021/jacs.2c04588] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A new strategy is described for the Lewis base-catalyzed bromochlorination of unsaturated systems that is mechanistically distinct from prior methodologies. The novelty of this method hinges on the utilization of thionyl chloride as a latent chloride source in combination with as little as 1 mol % of triphenylphosphine or triphenylphosphine oxide as Lewis basic activators. This metal-free, catalytic chemo-, regio-, and diastereoselective bromochlorination of alkenes and alkynes exhibits excellent site selectivity in polyunsaturated systems and provides access to a wide variety of vicinal bromochlorides with up to >20:1 regio- and diastereoselectivity. The precision installation of Br, Cl, and I in various combinations is also demonstrated by simply varying the commercial halogenating reagents employed. Notably, when a chiral Lewis base promoter is employed, an enantioselective bromochlorination of chalcones is possible with up to a 92:8 enantiomeric ratio when utilizing only 1-3 mol % of (DHQD)2PHAL.
Collapse
|
8
|
Li RN, Chen SL. Mechanism for the Halogenation and Azidation of Lysine Catalyzed by Non-heme Iron BesD Enzyme. Chem Asian J 2022; 17:e202200438. [PMID: 35763338 DOI: 10.1002/asia.202200438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/23/2022] [Indexed: 11/09/2022]
Abstract
Selective halogenation is important in synthetic chemistry. BesD, a new member of the non-heme Fe(II)/α-ketoglutarate (αKG)-dependent halogenase family, can activate the sp3 C-H bond and halogenate lysine, in particular without a carrier protein. Using the density functional calculations, a chlorination mechanism in BesD has been proposed, mainly including the formation of Cl-Fe(IV)=O through the αKG decarboxylation, the isomerization of Cl-Fe(IV)=O, the substrate hydrogen abstraction by Fe(IV)=O, and the rebound of chloro to the substrate carbon radical. The hydrogen abstraction is rate-limiting. The isomerization of Cl-Fe(IV)=O is essential for the hydrogen abstraction and the chiral selectivity. The BesD-catalyzed bromination and azidation of lysine adopt the same mechanism as the chlorination. The hardly-changed overall barriers indicate that the introduced ligands (X) do not affect the reaction rate significantly, implying that the X-introduced reactions catalyzed by BesD may be extended to other X anions.
Collapse
Affiliation(s)
- Rui-Ning Li
- Beijing Institute of Technology, School of Chemistry and Chemical Engineering, 100081, Beijing, CHINA
| | - Shi-Lu Chen
- Beijing Institute of Technology, School of Chemistry and Chemical Engineering, 5th, ZhongGuanCun South Street, 100081, Beijing, CHINA
| |
Collapse
|
9
|
Zheng Y, Zhang S, Low KH, Zi W, Huang Z. A Unified and Desymmetric Approach to Chiral Tertiary Alkyl Halides. J Am Chem Soc 2022; 144:1951-1961. [DOI: 10.1021/jacs.1c12404] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Yin Zheng
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
| | - Suihan Zhang
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
| | - Kam-Hung Low
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
| | - Weiwei Zi
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Zhongxing Huang
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
| |
Collapse
|
10
|
Lessard O, Lainé D, Fecteau CÉ, Johnson PA, Giguère D. Fundamental curiosity of multivicinal inter-halide stereocenters. Org Chem Front 2022. [DOI: 10.1039/d2qo01433e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A stereoselective strategy allowed the striking impact of a single halogen on the physical properties of inter-halide alkane units to be unravelled.
Collapse
Affiliation(s)
- Olivier Lessard
- Département de chimie, Université Laval, 1045 Avenue de la Médecine, Quebec City, QC, G1V0A6 Canada
| | - Danny Lainé
- Département de chimie, Université Laval, 1045 Avenue de la Médecine, Quebec City, QC, G1V0A6 Canada
| | - Charles-Émile Fecteau
- Département de chimie, Université Laval, 1045 Avenue de la Médecine, Quebec City, QC, G1V0A6 Canada
| | - Paul A. Johnson
- Département de chimie, Université Laval, 1045 Avenue de la Médecine, Quebec City, QC, G1V0A6 Canada
| | - Denis Giguère
- Département de chimie, Université Laval, 1045 Avenue de la Médecine, Quebec City, QC, G1V0A6 Canada
| |
Collapse
|
11
|
Abstract
The first example for the electrochemical cis‐dichlorination of alkenes is presented. The reaction can be performed with little experimental effort by using phenylselenyl chloride as catalyst and tetrabutylammoniumchloride as supporting electrolyte, which also acts as nucleophilic reagent for the SN2‐type replacement of selenium versus chloride. Cyclic voltammetric measurements and control experiments revealed a dual role of phenylselenyl chloride in the reaction. Based on these results a reaction mechanism was postulated, where the key step of the process is the activation of a phenylselenyl chloride‐alkene adduct by electrochemically generated phenylselenyl trichloride. Like this, different aliphatic and aromatic cyclic and acyclic alkenes were converted to the dichlorinated products. Thereby, throughout high diastereoselectivities were achieved for the cis‐chlorinated compounds of >95 : 5 or higher.
Collapse
Affiliation(s)
- Julia Strehl
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26111, Oldenburg, Germany
| | - Cornelius Fastie
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26111, Oldenburg, Germany
| | - Gerhard Hilt
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26111, Oldenburg, Germany
| |
Collapse
|
12
|
Ju W, Wang X, Tian H, Gui J. Asymmetric Total Synthesis of Clionastatins A and B. J Am Chem Soc 2021; 143:13016-13021. [PMID: 34398601 DOI: 10.1021/jacs.1c07511] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Herein we report the first total synthesis of polychlorinated steroids clionastatins A and B, which was accomplished asymmetrically by means of a convergent, radical fragment coupling approach. Key features of the synthesis include an Ireland-Claisen rearrangement to introduce the C5 stereocenter (which was ultimately transferred to the C10 quaternary stereocenter of the clionastatins via a traceless stereochemical relay), a regioselective acyl radical conjugate addition to join the two fragments, an intramolecular Heck reaction to install the C10 quaternary stereocenter, and a diastereoselective olefin dichlorination to establish the synthetically challenging pseudoequatorial dichlorides. This work also enabled us to determine that the true structures of clionastatins A and B are in fact C14 epimers of the originally proposed structures.
Collapse
Affiliation(s)
- Wei Ju
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Xudong Wang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Hailong Tian
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Jinghan Gui
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| |
Collapse
|
13
|
Lee GS, Kim D, Hong SH. Pd-catalyzed formal Mizoroki-Heck coupling of unactivated alkyl chlorides. Nat Commun 2021; 12:991. [PMID: 33579940 PMCID: PMC7881129 DOI: 10.1038/s41467-021-21270-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 01/15/2021] [Indexed: 11/09/2022] Open
Abstract
The use of alkyl chlorides in Pd-catalyzed Mizoroki-Heck coupling reactions remains an unsolved problem despite their significant potential for synthetic utility and applicability. The combination of the high thermodynamic barrier of alkyl chloride activation and kinetic propensity of alkylpalladium complexes to undergo undesired β-hydride elimination provides significant challenges. Herein, a variety of alkyl chlorides, even tertiary chlorides, are shown to efficiently participate in Mizoroki-Heck cross-coupling reactions with excellent functional group compatibility under mild reaction conditions via photoinduced Pd catalysis. The reaction is applied to late-stage functionalizations of diverse biologically significant scaffolds and iterative double Mizoroki-Heck annulations, affording high molecular complexity in a single step. Notably, studies on the kinetic isotope effects in combination with density functional theory (DFT)-computations completely exclude the involvement of a previously proposed β-hydride elimination in the catalytic cycle, revealing that the chlorine atom transfer process is the key catalytic turnover step. This distinctive single-electron transfer mediated reaction pathway resolves a longstanding challenge in traditional two-electron based Pd-catalyzed Mizoroki-Heck cross-coupling with alkyl electrophiles, wherein the β-hydride elimination is involved in the formation of both the desired product and undesired by-products.
Collapse
Affiliation(s)
- Geun Seok Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Daeun Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Soon Hyeok Hong
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
| |
Collapse
|
14
|
Bock J, Guria S, Wedek V, Hennecke U. Enantioselective Dihalogenation of Alkenes. Chemistry 2021; 27:4517-4530. [DOI: 10.1002/chem.202003176] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 09/01/2020] [Indexed: 01/17/2023]
Affiliation(s)
- Jonathan Bock
- Organic Chemistry Research Group (ORGC) Department of Chemistry and Department of Bioengineering Sciences Vrije Universiteit Brussel (VUB) Pleinlaan 2 1050 Brussels Belgium
| | - Sudip Guria
- Organic Chemistry Research Group (ORGC) Department of Chemistry and Department of Bioengineering Sciences Vrije Universiteit Brussel (VUB) Pleinlaan 2 1050 Brussels Belgium
| | - Volker Wedek
- Organic Chemistry Research Group (ORGC) Department of Chemistry and Department of Bioengineering Sciences Vrije Universiteit Brussel (VUB) Pleinlaan 2 1050 Brussels Belgium
| | - Ulrich Hennecke
- Organic Chemistry Research Group (ORGC) Department of Chemistry and Department of Bioengineering Sciences Vrije Universiteit Brussel (VUB) Pleinlaan 2 1050 Brussels Belgium
| |
Collapse
|
15
|
Sakai HA, Liu W, Le CC, MacMillan DWC. Cross-Electrophile Coupling of Unactivated Alkyl Chlorides. J Am Chem Soc 2020; 142:11691-11697. [PMID: 32564602 DOI: 10.1021/jacs.0c04812] [Citation(s) in RCA: 105] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Alkyl chlorides are bench-stable chemical feedstocks that remain among the most underutilized electrophile classes in transition metal catalysis. Overcoming intrinsic limitations of C(sp3)-Cl bond activation, we report the development of a novel organosilane reagent that can participate in chlorine atom abstraction under mild photocatalytic conditions. In particular, we describe the application of this mechanism to a dual nickel/photoredox catalytic protocol that enables the first cross-electrophile coupling of unactivated alkyl chlorides and aryl chlorides. Employing these low-toxicity, abundant, and commercially available organochloride building blocks, this methodology allows access to a broad array of highly functionalized C(sp2)-C(sp3) coupled adducts, including numerous drug analogues.
Collapse
Affiliation(s)
- Holt A Sakai
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
| | - Wei Liu
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
| | - Chi Chip Le
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
| | - David W C MacMillan
- Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States
| |
Collapse
|
16
|
Lanke V, Marek I. Nucleophilic Substitution at Quaternary Carbon Stereocenters. J Am Chem Soc 2020; 142:5543-5548. [DOI: 10.1021/jacs.0c01133] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Veeranjaneyulu Lanke
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City 3200009, Haifa, Israel
| | - Ilan Marek
- Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City 3200009, Haifa, Israel
| |
Collapse
|
17
|
Chen R, Yang S, Zhang Y. Recent progress in the total synthesis of marine brominated sesquiterpene aplydactone. Org Biomol Chem 2020; 18:1036-1045. [PMID: 31961356 DOI: 10.1039/c9ob02642h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aplydactone is a brominated sesquiterpene isolated from the sea hare Aplysia dactylomela. Structurally, it features a complex cage-like skeleton containing a highly strained tricyclic-[4.2.0.03,8]-4-decanone system. Its unique structural features have fascinated many synthetic chemists. In this review, the synthetic efforts towards aplydactone in the last five years are summarized in two categories including nonbiomimetic synthesis and biomimetic synthesis based on the core synthetic strategy. These syntheses set a classical and instructive example for the syntheses of other marine natural products.
Collapse
Affiliation(s)
- Renzhi Chen
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China.
| | - Sihan Yang
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China.
| | - Yandong Zhang
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China.
| |
Collapse
|
18
|
Liu C, Zhu C, Cai Y, Yang Z, Zeng H, Chen F, Jiang H. Fluorohalogenation of
gem
‐Difluoroalkenes: Synthesis and Applications of α‐Trifluoromethyl Halides. Chemistry 2020; 26:1953-1957. [DOI: 10.1002/chem.201905445] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Chi Liu
- Key Laboratory of Functional Molecular Engineering of, Guangdong Province School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 P. R. China
| | - Chuanle Zhu
- Key Laboratory of Functional Molecular Engineering of, Guangdong Province School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 P. R. China
| | - Yingying Cai
- Key Laboratory of Functional Molecular Engineering of, Guangdong Province School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 P. R. China
| | - Zhiyi Yang
- Key Laboratory of Functional Molecular Engineering of, Guangdong Province School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 P. R. China
| | - Hao Zeng
- Key Laboratory of Functional Molecular Engineering of, Guangdong Province School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 P. R. China
| | - Fulin Chen
- Key Laboratory of Functional Molecular Engineering of, Guangdong Province School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 P. R. China
| | - Huanfeng Jiang
- Key Laboratory of Functional Molecular Engineering of, Guangdong Province School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 P. R. China
| |
Collapse
|
19
|
Rosa GP, Tavares WR, Sousa PMC, Pagès AK, Seca AML, Pinto DCGA. Seaweed Secondary Metabolites with Beneficial Health Effects: An Overview of Successes in In Vivo Studies and Clinical Trials. Mar Drugs 2019; 18:E8. [PMID: 31861879 PMCID: PMC7024274 DOI: 10.3390/md18010008] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/16/2019] [Accepted: 12/18/2019] [Indexed: 12/13/2022] Open
Abstract
Macroalgae are increasingly viewed as a source of secondary metabolites with great potential for the development of new drugs. In this development, in vitro studies are only the first step in a long process, while in vivo studies and clinical trials are the most revealing stages of the true potential and limitations that a given metabolite may have as a new drug. This literature review aims to give a critical overview of the secondary metabolites that reveal the most interesting results in these two steps. Phlorotannins show great pharmaceutical potential in in vivo models and, among the several examples, the anti-dyslipidemia activity of dieckol must be highlighted because it was more effective than lovastatin in an in vivo model. The IRLIIVLMPILMA tridecapeptide that exhibits an in vivo level of activity similar to the hypotensive clinical drug captopril should still be stressed, as well as griffithsin which showed such stunning results over a variety of animal models and which will probably move onto clinical trials soon. Regarding clinical trials, studies with pure algal metabolites are scarce, limited to those carried out with kahalalide F and fucoxanthin. The majority of clinical trials currently aim to ascertain the effect of algae consumption, as extracts or fractions, on obesity and diabetes.
Collapse
Affiliation(s)
- Gonçalo P. Rosa
- cE3c—Centre for Ecology, Evolution and Environmental Changes/Azorean Biodiversity Group & University of Azores, Rua Mãe de Deus, 9501-801 Ponta Delgada, Portugal;
| | - Wilson R. Tavares
- Faculty of Sciences and Technology, University of Azores, 9501-801 Ponta Delgada, Portugal; (W.R.T.); (P.M.C.S.); (A.K.P.)
| | - Pedro M. C. Sousa
- Faculty of Sciences and Technology, University of Azores, 9501-801 Ponta Delgada, Portugal; (W.R.T.); (P.M.C.S.); (A.K.P.)
| | - Aida K. Pagès
- Faculty of Sciences and Technology, University of Azores, 9501-801 Ponta Delgada, Portugal; (W.R.T.); (P.M.C.S.); (A.K.P.)
| | - Ana M. L. Seca
- cE3c—Centre for Ecology, Evolution and Environmental Changes/Azorean Biodiversity Group & University of Azores, Rua Mãe de Deus, 9501-801 Ponta Delgada, Portugal;
- QOPNA & LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Diana C. G. A. Pinto
- QOPNA & LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
| |
Collapse
|
20
|
El Gaafary M, Hafner S, Lang SJ, Jin L, Sabry OM, Vogel CV, Vanderwal CD, Syrovets T, Simmet T. A Novel Polyhalogenated Monoterpene Induces Cell Cycle Arrest and Apoptosis in Breast Cancer Cells. Mar Drugs 2019; 17:md17080437. [PMID: 31349625 PMCID: PMC6723102 DOI: 10.3390/md17080437] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 07/17/2019] [Accepted: 07/23/2019] [Indexed: 12/13/2022] Open
Abstract
Breast cancer is the most common cancer type and a primary cause of cancer mortality among females worldwide. Here, we analyzed the anticancer efficacy of a novel bromochlorinated monoterpene, PPM1, a synthetic analogue of polyhalogenated monoterpenes from Plocamium red algae and structurally similar non-brominated monoterpenes. PPM1, but not the non-brominated monoterpenes, decreased selectively the viability of several triple-negative as well as triple-positive breast cancer cells with different p53 status without significantly affecting normal breast epithelial cells. PPM1 induced accumulation of triple-negative MDA-MB-231 cells with 4N DNA content characterized by decreased histone H3-S10/T3 phosphorylation indicating cell cycle arrest in the G2 phase. Western immunoblot analysis revealed that PPM1 treatment triggered an initial rapid activation of Aurora kinases A/B/C and p21Waf1/Cip1 accumulation, which was followed by accumulation of polyploid >4N cells. Flow cytometric analysis showed mitochondrial potential disruption, caspase 3/7 activation, phosphatidylserine externalization, reduction of the amount polyploid cells, and DNA fragmentation consistent with induction of apoptosis. Cell viability was partially restored by the pan-caspase inhibitor Z-VAD-FMK indicating caspase contribution. In vivo, PPM1 inhibited growth, proliferation, and induced apoptosis in MDA-MB-231 xenografted onto the chick chorioallantoic membrane. Hence, Plocamium polyhalogenated monoterpenes and synthetic analogues deserve further exploration as promising anticancer lead compounds.
Collapse
Affiliation(s)
- Menna El Gaafary
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, D-89081 Ulm, Germany
- Department of Pharmacognosy, College of Pharmacy, Cairo University, Cairo 11562, Egypt
| | - Susanne Hafner
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, D-89081 Ulm, Germany
| | - Sophia J Lang
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, D-89081 Ulm, Germany
| | - Lu Jin
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, D-89081 Ulm, Germany
| | - Omar M Sabry
- Department of Pharmacognosy, College of Pharmacy, Cairo University, Cairo 11562, Egypt
| | - Carl V Vogel
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, CA 92697-2025, USA
| | - Christopher D Vanderwal
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, CA 92697-2025, USA
| | - Tatiana Syrovets
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, D-89081 Ulm, Germany.
| | - Thomas Simmet
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, D-89081 Ulm, Germany.
| |
Collapse
|
21
|
Lefranc F, Koutsaviti A, Ioannou E, Kornienko A, Roussis V, Kiss R, Newman D. Algae metabolites: from in vitro growth inhibitory effects to promising anticancer activity. Nat Prod Rep 2019; 36:810-841. [PMID: 30556575 DOI: 10.1039/c8np00057c] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Covering: 1957 to 2017 Algae constitute a heterogeneous group of eukaryotic photosynthetic organisms, mainly found in the marine environment. Algae produce numerous metabolites that help them cope with the harsh conditions of the marine environment. Because of their structural diversity and uniqueness, these molecules have recently gained a lot of interest for the identification of medicinally useful agents, including those with potential anticancer activities. In the current review, which is not a catalogue-based one, we first highlight the major biological events that lead to various types of cancer, including metastatic ones, to chemoresistance, thus to any types of current anticancer treatment relating to the use of chemotherapeutics. We then review algal metabolites for which scientific literature reports anticancer activity. Lastly, we focus on algal metabolites with promising anticancer activity based on their ability to target biological characteristics of cancer cells responsible for poor treatment outcomes. Thus, we highlight compounds that have, among others, one or more of the following characteristics: selectivity in reducing the proliferation of cancer cells over normal ones, potential for killing cancer cells through non-apoptotic signaling pathways, ability to circumvent MDR-related efflux pumps, and activity in vivo in relevant pre-clinical models.
Collapse
Affiliation(s)
- Florence Lefranc
- Service de Neurochirurgie, Hôpital Erasme, ULB, 1070 Brussels, Belgium.
| | | | | | | | | | | | | |
Collapse
|
22
|
Jia Y, Chen L, Zhang H, Zheng Y, Jiang ZX, Yang Z. Electrophilic chloro(ω-alkoxy)lation of alkenes employing 1-chloro-1,2-benziodoxol-3-one: facile synthesis of β-chloroethers. Org Biomol Chem 2019; 16:7203-7213. [PMID: 30255191 DOI: 10.1039/c8ob01634h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A four-component reaction for electrophilic chloro(ω-alkoxy)lation of alkenes has been described. The stable chloro-iodine(iii) reagent and SOCl2 were used as electrophilic and nucleophilic chlorine sources, respectively. This approach provides a straightforward way to synthesize various useful β-chloro ω-chloroalkyl ethers from a wide range of alkenes, including electron-deficient, aromatic and unactivated alkenes. The synthetic applications of this approach were also explored in some useful transformations.
Collapse
Affiliation(s)
- Yimin Jia
- Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, P. R. China.
| | | | | | | | | | | |
Collapse
|
23
|
Abstract
A concise and selective synthesis of the dichlorinated meroterpenoid azamerone is described. The paucity of tactics for the synthesis of natural-product-relevant chiral organochlorides motivated the development of unique strategies for accessing these motifs in enantioenriched forms. The route features a novel enantioselective chloroetherification reaction, a Pd-catalyzed cross-coupling between a quinone diazide and a boronic hemiester, and a late-stage tetrazine [4+2]-cycloaddition/oxidation cascade.
Collapse
Affiliation(s)
- Matthew L Landry
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Grace M McKenna
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Noah Z Burns
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| |
Collapse
|
24
|
McKinnie SMK, Miles ZD, Jordan PA, Awakawa T, Pepper HP, Murray LAM, George JH, Moore BS. Total Enzyme Syntheses of Napyradiomycins A1 and B1. J Am Chem Soc 2018; 140:17840-17845. [PMID: 30525563 DOI: 10.1021/jacs.8b10134] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The biosynthetic route to the napyradiomycin family of bacterial meroterpenoids has been fully described 32 years following their original isolation and 11 years after their gene cluster discovery. The antimicrobial and cytotoxic natural products napyradiomycins A1 and B1 are produced using three organic substrates (1,3,6,8-tetrahydroxynaphthalene, dimethylallyl pyrophosphate, and geranyl pyrophosphate), and catalysis via five enzymes: two aromatic prenyltransferases (NapT8 and T9); and three vanadium dependent haloperoxidase (VHPO) homologues (NapH1, H3, and H4). Building upon the previous characterization of NapH1, H3, and T8, we herein describe the initial (NapT9, H1) and final (NapH4) steps required for napyradiomycin construction. This remarkably streamlined biosynthesis highlights the utility of VHPO enzymology in complex natural product generation, as NapH4 efficiently performs a unique chloronium-induced terpenoid cyclization to establish two stereocenters and a new carbon-carbon bond, and dual-acting NapH1 catalyzes chlorination and etherification reactions at two distinct stages of the pathway. Moreover, we employed recombinant napyradiomycin biosynthetic enzymes to chemoenzymatically synthesize milligram quantities in one pot in 1 day. This method represents a viable enantioselective approach to produce complex halogenated metabolites, like napyradiomycin B1, that have yet to be chemically synthesized.
Collapse
Affiliation(s)
- Shaun M K McKinnie
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego , La Jolla , California 92093 , United States
| | - Zachary D Miles
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego , La Jolla , California 92093 , United States
| | - Peter A Jordan
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego , La Jolla , California 92093 , United States
| | - Takayoshi Awakawa
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego , La Jolla , California 92093 , United States
| | - Henry P Pepper
- Department of Chemistry , University of Adelaide , Adelaide , South Australia 5005 , Australia
| | - Lauren A M Murray
- Department of Chemistry , University of Adelaide , Adelaide , South Australia 5005 , Australia
| | - Jonathan H George
- Department of Chemistry , University of Adelaide , Adelaide , South Australia 5005 , Australia
| | - Bradley S Moore
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego , La Jolla , California 92093 , United States.,Skaggs School of Pharmacy and Pharmaceutical Sciences , University of California San Diego , La Jolla , California 92093 , United States
| |
Collapse
|
25
|
Seidl FJ, Min C, Lopez JA, Burns NZ. Catalytic Regio- and Enantioselective Haloazidation of Allylic Alcohols. J Am Chem Soc 2018; 140:15646-15650. [PMID: 30403852 DOI: 10.1021/jacs.8b10799] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Herein we report a highly regio- and stereoselective haloazidation of allylic alcohols. This enantioselective reaction uses readily available materials and can be performed on a variety of alkyl-substituted alkenes and can incorporate either bromine or chlorine as the electrophilic halogen component. Both halide and azido groups of the resulting products can be transformed into valuable building blocks with complete stereospecificity. The first example of an enantioselective 1,4-haloazidation of a conjugated diene is reported as well as its application to a concise synthesis of an aza-sugar.
Collapse
Affiliation(s)
- Frederick J Seidl
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Chang Min
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Jovan A Lopez
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Noah Z Burns
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| |
Collapse
|
26
|
Zhong F, Yue WJ, Zhang HJ, Zhang CY, Yin L. Catalytic Asymmetric Construction of Halogenated Stereogenic Carbon Centers by Direct Vinylogous Mannich-Type Reaction. J Am Chem Soc 2018; 140:15170-15175. [DOI: 10.1021/jacs.8b09484] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Feng Zhong
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Wen-Jun Yue
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Hai-Jun Zhang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Cheng-Yuan Zhang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Liang Yin
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| |
Collapse
|
27
|
Seaweed Secondary Metabolites In Vitro and In Vivo Anticancer Activity. Mar Drugs 2018; 16:md16110410. [PMID: 30373208 PMCID: PMC6266495 DOI: 10.3390/md16110410] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 10/22/2018] [Accepted: 10/23/2018] [Indexed: 12/21/2022] Open
Abstract
Isolation, finding or discovery of novel anticancer agents is very important for cancer treatment, and seaweeds are one of the largest producers of chemically active metabolites with valuable cytotoxic properties, and therefore can be used as new chemotherapeutic agents or source of inspiration to develop new ones. Identification of the more potent and selective anticancer components isolated from brown, green and red seaweeds, as well as studies of their mode of action is very attractive and constitute a small but relevant progress for pharmacological applications. Several researchers have carried out in vitro and in vivo studies in various cell lines and have disclosed the active metabolites among the terpenoids, including carotenoids, polyphenols and alkaloids that can be found in seaweeds. In this review the type of metabolites and their cytotoxic or antiproliferative effects will be discussed additionally their mode of action, structure-activity relationship and selectivity will also be revealed. The diterpene dictyolactone, the sterol cholest-5-en-3β,7α-diol and the halogenated monoterpene halomon are among the reported compounds, the ones that present sub-micromolar cytotoxicity. Additionally, one dimeric sesquiterpene of the cyclolaurane-type, three bromophenols and one halogenated monoterpene should be emphasized because they exhibit half maximal inhibitory concentration (IC50) values between 1–5 µM against several cell lines.
Collapse
|
28
|
Horibe T, Tsuji Y, Ishihara K. Thiourea–I2 as Lewis Base–Lewis Acid Cooperative Catalysts for Iodochlorination of Alkene with In Situ-Generated I–Cl. ACS Catal 2018. [DOI: 10.1021/acscatal.8b01565] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Takahiro Horibe
- Graduate School of Engineering, Nagoya University, B2-3(611), Furo-cho, Chikusa, Nagoya 464-8603, Japan
| | - Yasutaka Tsuji
- Graduate School of Engineering, Nagoya University, B2-3(611), Furo-cho, Chikusa, Nagoya 464-8603, Japan
| | - Kazuaki Ishihara
- Graduate School of Engineering, Nagoya University, B2-3(611), Furo-cho, Chikusa, Nagoya 464-8603, Japan
| |
Collapse
|
29
|
Abstract
To date, more than 5000 biogenic halogenated molecules have been characterized. This number continues to increase as chemists explore chloride- and bromide-rich marine environments in search of novel bioactive natural products. Naturally occurring organohalogens span nearly all biosynthetic structural classes, exhibit a range of unique biological activities, and have been the subject of numerous investigations. Despite the abundance of and interest in halogenated molecules, enantioselective methods capable of forging carbon-halogen bonds in synthetically relevant contexts remain scarce. Accordingly, syntheses of organohalogens often rely on multistep functional group interconversions to establish carbon-halogen stereocenters. Our group has developed an enantioselective dihalogenation reaction and utilized it in the only reported examples of catalytic enantioselective halogenation in natural product synthesis. In this Account, we describe our laboratory's development of a method for catalytic, enantioselective dihalogenation and the application of this method to the synthesis of both mono- and polyhalogenated natural products. In the first part, we describe the initial discovery of a TADDOL-mediated dibromination of cinnamyl alcohols. Extension of this reaction to a second-generation system capable of selective bromochlorination, dichlorination, and dibromination is then detailed. This system is capable of controlling the enantioselectivity of dihalide formation, chemoselectivity for polyolefinic substrates, and regioselectivity in the case of bromochlorination. The ability of this method to exert control over regioselectivity of halide delivery permits selective halogenation of electronically nonbiased olefins required for total synthesis. In the second part, we demonstrate how the described dihalogenation has provided efficient access to a host of structurally diverse natural products. The most direct application of this methodology is in the synthesis of naturally occurring vicinal dihalides. Chiral vicinal bromochlorides represent a class of >175 natural products; syntheses of five members of this class, including its flagship member, (+)-halomon, have been accomplished through use of the catalytic, enantioselective bromochlorination. Likewise, enantioselective dichlorination has provided selective access to two members of the chlorosulfolipids, a class of linear, acyclic polychlorides. Synthesis of chiral monohalides has been achieved through solvolysis of enantioenriched bromochlorides; this approach has resulted in the synthesis of five bromocyclohexane-containing natural products through an enantiospecific bromopolyene cyclization. In reviewing these syntheses, a framework for the synthesis of chiral organohalogens mediated by catalytic, enantioselective dihalogenation has emerged. The development of a selective dihalogenation method has been highly enabling in the synthesis of halogenated natural products. In this Account, we detail all examples of catalytic, enantioselective halogenation in total synthesis and encourage the further development of synthetically useful halogenation methodologies.
Collapse
Affiliation(s)
- Matthew L. Landry
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Noah Z. Burns
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| |
Collapse
|
30
|
Wu X, Iwata T, Scharf A, Qin T, Reichl KD, Porco JA. Asymmetric Synthesis of Gonytolide A: Strategic Use of an Aryl Halide Blocking Group for Oxidative Coupling. J Am Chem Soc 2018; 140:5969-5975. [PMID: 29658717 PMCID: PMC5943148 DOI: 10.1021/jacs.8b02535] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The first synthesis of the chromanone lactone dimer gonytolide A has been achieved employing vanadium(V)-mediated oxidative coupling of the monomer gonytolide C. An o-bromine blocking group strategy was employed to favor para- para coupling and to enable kinetic resolution of (±)-gonytolide C. Asymmetric conjugate reduction enabled practical kinetic resolution of a chiral, racemic precursor and the asymmetric synthesis of (+)-gonytolide A and its atropisomer.
Collapse
Affiliation(s)
| | | | - Adam Scharf
- Department of Chemistry and Center for Molecular Discovery (BU-CMD),
Boston University, Boston, Massachusetts 02215, United States
| | - Tian Qin
- Department of Chemistry and Center for Molecular Discovery (BU-CMD),
Boston University, Boston, Massachusetts 02215, United States
| | - Kyle D. Reichl
- Department of Chemistry and Center for Molecular Discovery (BU-CMD),
Boston University, Boston, Massachusetts 02215, United States
| | - John A. Porco
- Department of Chemistry and Center for Molecular Discovery (BU-CMD),
Boston University, Boston, Massachusetts 02215, United States
| |
Collapse
|
31
|
Affiliation(s)
- Sukalyan Bhadra
- Inorganic Materials and Catalysis Division, Academy of Scientific and Innovative Research, CSIR-Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar, 364002 Gujarat, India
| | - Hisashi Yamamoto
- Molecular Catalyst Research Center, Chubu University, 1200, Matsumoto-Cho, Kasugai, Aichi 487-8501, Japan
| |
Collapse
|
32
|
Ferrocene derivatives of liquid chiral molecules allow assignment of absolute configuration by X-ray crystallography. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.tetasy.2017.09.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
33
|
Burckle AJ, Gál B, Seidl FJ, Vasilev VH, Burns NZ. Enantiospecific Solvolytic Functionalization of Bromochlorides. J Am Chem Soc 2017; 139:13562-13569. [PMID: 28858493 PMCID: PMC5987033 DOI: 10.1021/jacs.7b07792] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Herein, we report that under mild solvolytic conditions, enantioenriched bromochlorides can be ionized, stereospecifically cyclized to an array of complex bromocyclic scaffolds, or intermolecularly trapped by exogenous nucleophiles. Mechanistic investigations support an ionic mechanism wherein the bromochloride serves as an enantioenriched bromonium surrogate. Several natural product-relevant motifs are accessed in enantioenriched form for the first time with high levels of stereocontrol, and this technology is applied to the scalable synthesis of a polycyclic brominated natural product. Arrays of nucleophiles including olefins, alkynes, heterocycles, and epoxides are competent traps in the bromonium-induced cyclizations, leading to the formation of enantioenriched mono-, bi-, and tricyclic products. This strategy is further amenable to intermolecular coupling between cinnamyl bromochlorides and a diverse set of commercially available nucleophiles. Collectively, this work demonstrates that enantioenriched bromonium chlorides are configurationally stable under solvolytic conditions in the presence of a variety of functional groups.
Collapse
Affiliation(s)
- Alexander J. Burckle
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Bálint Gál
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Frederick J. Seidl
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Vasil H. Vasilev
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Noah Z. Burns
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| |
Collapse
|
34
|
Abstract
Covering: 2015. Previous review: Nat. Prod. Rep., 2016, 33, 382-431This review covers the literature published in 2015 for marine natural products (MNPs), with 1220 citations (792 for the period January to December 2015) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1340 in 429 papers for 2015), together with the relevant biological activities, source organisms and country of origin. Reviews, biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.
Collapse
Affiliation(s)
- John W Blunt
- Department of Chemistry, University of Canterbury, Christchurch, New Zealand.
| | - Brent R Copp
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Robert A Keyzers
- Centre for Biodiscovery, School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Murray H G Munro
- Department of Chemistry, University of Canterbury, Christchurch, New Zealand.
| | - Michèle R Prinsep
- Chemistry, School of Science, University of Waikato, Hamilton, New Zealand
| |
Collapse
|
35
|
Agarwal V, Miles ZD, Winter JM, Eustáquio AS, El Gamal AA, Moore BS. Enzymatic Halogenation and Dehalogenation Reactions: Pervasive and Mechanistically Diverse. Chem Rev 2017; 117:5619-5674. [PMID: 28106994 PMCID: PMC5575885 DOI: 10.1021/acs.chemrev.6b00571] [Citation(s) in RCA: 235] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Naturally produced halogenated compounds are ubiquitous across all domains of life where they perform a multitude of biological functions and adopt a diversity of chemical structures. Accordingly, a diverse collection of enzyme catalysts to install and remove halogens from organic scaffolds has evolved in nature. Accounting for the different chemical properties of the four halogen atoms (fluorine, chlorine, bromine, and iodine) and the diversity and chemical reactivity of their organic substrates, enzymes performing biosynthetic and degradative halogenation chemistry utilize numerous mechanistic strategies involving oxidation, reduction, and substitution. Biosynthetic halogenation reactions range from simple aromatic substitutions to stereoselective C-H functionalizations on remote carbon centers and can initiate the formation of simple to complex ring structures. Dehalogenating enzymes, on the other hand, are best known for removing halogen atoms from man-made organohalogens, yet also function naturally, albeit rarely, in metabolic pathways. This review details the scope and mechanism of nature's halogenation and dehalogenation enzymatic strategies, highlights gaps in our understanding, and posits where new advances in the field might arise in the near future.
Collapse
Affiliation(s)
- Vinayak Agarwal
- Center for Oceans and Human Health, Scripps Institution of Oceanography, University of California, San Diego
| | - Zachary D. Miles
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego
| | | | - Alessandra S. Eustáquio
- College of Pharmacy, Department of Medicinal Chemistry & Pharmacognosy and Center for Biomolecular Sciences, University of Illinois at Chicago
| | - Abrahim A. El Gamal
- Center for Oceans and Human Health, Scripps Institution of Oceanography, University of California, San Diego
| | - Bradley S. Moore
- Center for Oceans and Human Health, Scripps Institution of Oceanography, University of California, San Diego
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego
| |
Collapse
|
36
|
Tan Y, Luo S, Li D, Zhang N, Jia S, Liu Y, Qin W, Song CE, Yan H. Enantioselective Synthesis of anti–syn-Trihalides and anti–syn–anti-Tetrahalides via Asymmetric β-Elimination. J Am Chem Soc 2017; 139:6431-6436. [DOI: 10.1021/jacs.7b02076] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Yu Tan
- Innovative Drug
Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Shilong Luo
- Innovative Drug
Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Dongmei Li
- Innovative Drug
Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Nan Zhang
- Innovative Drug
Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Shiqi Jia
- Innovative Drug
Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Yidong Liu
- Innovative Drug
Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Wenling Qin
- Innovative Drug
Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Choong Eui Song
- Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Korea
| | - Hailong Yan
- Innovative Drug
Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| |
Collapse
|
37
|
Kutateladze AG, Reddy DS. High-Throughput in Silico Structure Validation and Revision of Halogenated Natural Products Is Enabled by Parametric Corrections to DFT-Computed 13C NMR Chemical Shifts and Spin-Spin Coupling Constants. J Org Chem 2017; 82:3368-3381. [PMID: 28339201 DOI: 10.1021/acs.joc.7b00188] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Halogenated natural products constitute diverse and promising feedstock for molecular pharmaceuticals. However, their solution-structure elucidation by NMR presents several challenges, including the lack of fast methods to compute 13C chemical shifts for carbons bearing heavy atoms. We show that parametric corrections to DFT-computed chemical shifts in conjunction with rff-computed spin-spin coupling constants allow for fast and reliable screening of a large number of reported halogenated natural products, resulting in expedient structure validation or revision. In this paper, we examine more than 100 structures of halogenated terpenoids and other natural products with the new parametric approach and demonstrate that the accuracy of the combined method is sufficient to identify misassignments and suggest revisions in most cases (16 structures are revised). As the 1D 1H and 13C NMR data are ubiquitous and most routinely used in solution structure elucidation, this fast and efficient two-criterion method (nuclear spin-spin coupling and 13C chemical shifts) which we term DU8+ is recommended as the first essential step in structure assignment and validation.
Collapse
Affiliation(s)
- Andrei G Kutateladze
- Department of Chemistry and Biochemistry, University of Denver , Denver, Colorado 80208, United States
| | - D Sai Reddy
- Department of Chemistry and Biochemistry, University of Denver , Denver, Colorado 80208, United States
| |
Collapse
|
38
|
Sempere Molina Y, Ruchti J, Carreira EM. Enantioselective Addition of Alkynes to α,α-Dichlorinated Aldehydes. Org Lett 2017; 19:743-745. [PMID: 28127958 DOI: 10.1021/acs.orglett.6b03692] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Enantioselective addition of terminal alkynes to α,α-dichlorinated aldehydes employing Zn(OTf)2/NME is disclosed. The propargylic alcohols obtained are accessed in good yields and high enantioselectivity from easily accessible α,α-dichloroaldehydes. The method opens new strategic opportunities for the synthesis of chlorinated natural products, such as the chlorosulfolipids.
Collapse
Affiliation(s)
- Yeshua Sempere Molina
- Laboratorium für Organische Chemie, ETH Zürich , Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Jonathan Ruchti
- Laboratorium für Organische Chemie, ETH Zürich , Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Erick M Carreira
- Laboratorium für Organische Chemie, ETH Zürich , Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| |
Collapse
|
39
|
Soltanzadeh B, Jaganathan A, Yi Y, Yi H, Staples RJ, Borhan B. Highly Regio- and Enantioselective Vicinal Dihalogenation of Allyl Amides. J Am Chem Soc 2017; 139:2132-2135. [PMID: 28112919 PMCID: PMC7790169 DOI: 10.1021/jacs.6b09203] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We report a highly regio-, diastereo- and enantioselective vicinal dihalogenation of allyl amides. E- and Z-alkenes with both aryl and alkyl substituents were compatible with this chemistry. This is the result of exquisite catalyst controlled regioselectivity enabling use of electronically unbiased substrates. The reaction employs commercially available catalysts and halenium sources along with cheap inorganic halide salts to affect this transformation. A preliminary effort to extend this chemistry to heterodihalogenation is also presented.
Collapse
Affiliation(s)
- Bardia Soltanzadeh
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Arvind Jaganathan
- Dow Agrosciences LLC, 9330 Zionsville Road, Indianapolis, Indiana 46268, United States
| | - Yi Yi
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Hajoon Yi
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Richard J. Staples
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Babak Borhan
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| |
Collapse
|
40
|
Gál B, Bucher C, Burns NZ. Chiral Alkyl Halides: Underexplored Motifs in Medicine. Mar Drugs 2016; 14:md14110206. [PMID: 27827902 PMCID: PMC5128749 DOI: 10.3390/md14110206] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 10/21/2016] [Accepted: 10/31/2016] [Indexed: 11/21/2022] Open
Abstract
While alkyl halides are valuable intermediates in synthetic organic chemistry, their use as bioactive motifs in drug discovery and medicinal chemistry is rare in comparison. This is likely attributable to the common misconception that these compounds are merely non-specific alkylators in biological systems. A number of chlorinated compounds in the pharmaceutical and food industries, as well as a growing number of halogenated marine natural products showing unique bioactivity, illustrate the role that chiral alkyl halides can play in drug discovery. Through a series of case studies, we demonstrate in this review that these motifs can indeed be stable under physiological conditions, and that halogenation can enhance bioactivity through both steric and electronic effects. Our hope is that, by placing such compounds in the minds of the chemical community, they may gain more traction in drug discovery and inspire more synthetic chemists to develop methods for selective halogenation.
Collapse
Affiliation(s)
- Bálint Gál
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA 94305, USA.
| | - Cyril Bucher
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA 94305, USA.
| | - Noah Z Burns
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA 94305, USA.
| |
Collapse
|
41
|
Speck K, Wildermuth R, Magauer T. Convergent Assembly of the Tetracyclic Meroterpenoid (−)-Cyclosmenospongine by a Non-Biomimetic Polyene Cyclization. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201608040] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Klaus Speck
- Department of Chemistry and Pharmacy; Ludwig Maximilians University Munich; Butenandtstrasse 5-13 81377 Munich Germany
| | - Raphael Wildermuth
- Department of Chemistry and Pharmacy; Ludwig Maximilians University Munich; Butenandtstrasse 5-13 81377 Munich Germany
| | - Thomas Magauer
- Department of Chemistry and Pharmacy; Ludwig Maximilians University Munich; Butenandtstrasse 5-13 81377 Munich Germany
| |
Collapse
|
42
|
Speck K, Wildermuth R, Magauer T. Convergent Assembly of the Tetracyclic Meroterpenoid (-)-Cyclosmenospongine by a Non-Biomimetic Polyene Cyclization. Angew Chem Int Ed Engl 2016; 55:14131-14135. [PMID: 27730742 DOI: 10.1002/anie.201608040] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Indexed: 11/12/2022]
Abstract
The cationic cyclization of polyenes constitutes a powerful and elegant transformation, which has been utilized by nature's biosynthetic machinery for the construction of complex polycyclic terpenoids. Previous studies by chemists to mimic this cyclization in the laboratory were limited to different modes of activation using biosynthetic-like precursors, which accommodate only simple methyl-derived substituents. Here we describe the development of an unprecedented and highly efficient polyene cyclization of an aryl enol ether containing substrate. The cyclization was shown to proceed in a stepwise manner to generate three rings and three consecutive stereocenters, two of which are tetrasubstituted, in a single flask. The developed transformation is of great synthetic value and has enabled the convergent assembly of the tetracyclic meroterpenoid (-)-cyclosmenospongine.
Collapse
Affiliation(s)
- Klaus Speck
- Department of Chemistry and Pharmacy, Ludwig Maximilians University Munich, Butenandtstrasse 5-13, 81377, Munich, Germany
| | - Raphael Wildermuth
- Department of Chemistry and Pharmacy, Ludwig Maximilians University Munich, Butenandtstrasse 5-13, 81377, Munich, Germany
| | - Thomas Magauer
- Department of Chemistry and Pharmacy, Ludwig Maximilians University Munich, Butenandtstrasse 5-13, 81377, Munich, Germany.
| |
Collapse
|
43
|
Burckle AJ, Vasilev VH, Burns NZ. A Unified Approach for the Enantioselective Synthesis of the Brominated Chamigrene Sesquiterpenes. Angew Chem Int Ed Engl 2016; 55:11476-9. [PMID: 27506430 PMCID: PMC5505624 DOI: 10.1002/anie.201605722] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Indexed: 11/09/2022]
Abstract
The brominated chamigrene sesquiterpenes constitute a large subclass of bromocyclohexane-containing natural products, yet no general enantioselective strategy for the synthesis of these small molecules exists. Herein we report a general strategy for accessing this family of secondary metabolites, including the enantioselective synthesis of (-)-α- and (-)-ent-β-bromochamigrene, (-)-dactylone, and (+)-aplydactone. Access to these molecules is enabled by a stereospecific bromopolyene cyclization initiated by the solvolysis of an enantiomerically enriched vicinal bromochloride.
Collapse
Affiliation(s)
- Alexander J Burckle
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305, USA
| | - Vasil H Vasilev
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305, USA
| | - Noah Z Burns
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305, USA.
| |
Collapse
|
44
|
Hugelshofer CL, Magauer T. A Divergent Approach to the Marine Diterpenoids (+)-Dictyoxetane and (+)-Dolabellane V. Chemistry 2016; 22:15125-15136. [DOI: 10.1002/chem.201603061] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Indexed: 12/26/2022]
Affiliation(s)
- Cedric L. Hugelshofer
- Department of Chemistry and Pharmacy; Ludwig-Maximilians-University Munich; Butenandtstrasse 5-13 81377 Munich Germany
| | - Thomas Magauer
- Department of Chemistry and Pharmacy; Ludwig-Maximilians-University Munich; Butenandtstrasse 5-13 81377 Munich Germany
| |
Collapse
|
45
|
Burckle AJ, Vasilev VH, Burns NZ. A Unified Approach for the Enantioselective Synthesis of the Brominated Chamigrene Sesquiterpenes. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605722] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Alexander J. Burckle
- Department of Chemistry Stanford University 333 Campus Drive Stanford CA 94305 USA
| | - Vasil H. Vasilev
- Department of Chemistry Stanford University 333 Campus Drive Stanford CA 94305 USA
| | - Noah Z. Burns
- Department of Chemistry Stanford University 333 Campus Drive Stanford CA 94305 USA
| |
Collapse
|
46
|
Saska J, Lewis W, Paton RS, Denton RM. Synthesis of malhamensilipin A exploiting iterative epoxidation/chlorination: experimental and computational analysis of epoxide-derived chloronium ions. Chem Sci 2016; 7:7040-7049. [PMID: 28337338 PMCID: PMC5282550 DOI: 10.1039/c6sc03012b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 08/02/2016] [Indexed: 11/21/2022] Open
Abstract
We report a 12-step catalytic enantioselective formal synthesis of malhamensilipin A (3) based upon an iterative epoxidation/chlorination strategy.
We report a 12-step catalytic enantioselective formal synthesis of malhamensilipin A (3) and diastereoisomeric analogues from (E)-2-undecenal. The convergent synthesis relied upon iterative epoxidation and phosphorus(v)-mediated deoxydichlorination reactions as well a titanium-mediated epoxide-opening to construct the C11–C16 stereohexad. The latter transformation occurred with very high levels of stereoretention regardless of the C13 configuration of the parent epoxide, implicating anchimeric assistance of either the γ- or δ-chlorine atoms, and the formation of chloretanium or chlorolanium ions, respectively. A computational analysis of the chloronium ion intermediates provided support for the involvement of chlorolanium ions, whereas the potential chloretanium ions were found to be less likely intermediates on the basis of their greater carbocationic character.
Collapse
Affiliation(s)
- J Saska
- School of Chemistry , University Park , Nottingham , NG7 2RD , UK .
| | - W Lewis
- School of Chemistry , University Park , Nottingham , NG7 2RD , UK .
| | - R S Paton
- Chemistry Research Laboratory , 12 Mansfield Road , Oxford OX1 3TA , UK .
| | - R M Denton
- School of Chemistry , University Park , Nottingham , NG7 2RD , UK .
| |
Collapse
|
47
|
Seidl FJ, Burns NZ. Selective bromochlorination of a homoallylic alcohol for the total synthesis of (-)-anverene. Beilstein J Org Chem 2016; 12:1361-5. [PMID: 27559385 PMCID: PMC4979643 DOI: 10.3762/bjoc.12.129] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 06/23/2016] [Indexed: 11/23/2022] Open
Abstract
The scope of a recently reported method for the catalytic enantioselective bromochlorination of allylic alcohols is expanded to include a specific homoallylic alcohol. Critical factors for optimization of this reaction are highlighted. The utility of the product bromochloride is demonstrated by the first total synthesis of an antibacterial polyhalogenated monoterpene, (-)-anverene.
Collapse
Affiliation(s)
- Frederick J Seidl
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Noah Z Burns
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| |
Collapse
|
48
|
Landry ML, Hu DX, McKenna GM, Burns NZ. Catalytic Enantioselective Dihalogenation and the Selective Synthesis of (-)-Deschloromytilipin A and (-)-Danicalipin A. J Am Chem Soc 2016; 138:5150-8. [PMID: 27018981 PMCID: PMC4922634 DOI: 10.1021/jacs.6b01643] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A titanium-based catalytic enantioselective dichlorination of simple allylic alcohols is described. This dichlorination reaction provides stereoselective access to all common dichloroalcohol building blocks used in syntheses of chlorosulfolipid natural products. An enantioselective synthesis of ent-(-)-deschloromytilipin A and a concise, eight-step synthesis of ent-(-)-danicalipin A are executed and employ the dichlorination reaction as the first step. Extension of this system to enantioselective dibromination and its use in the synthesis of pentabromide stereoarrays relevant to bromosulfolipids is reported. The described dichlorination and dibromination reactions are capable of exerting diastereocontrol in complex settings allowing X-ray crystal structure analysis of natural and unnatural diastereomers of polyhalogenated stereohexads.
Collapse
Affiliation(s)
- Matthew L. Landry
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Dennis X. Hu
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Grace M. McKenna
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Noah Z. Burns
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| |
Collapse
|
49
|
Chung WJ, Vanderwal CD. Stereoselective Halogenation in Natural Product Synthesis. Angew Chem Int Ed Engl 2016; 55:4396-434. [PMID: 26833878 PMCID: PMC6028003 DOI: 10.1002/anie.201506388] [Citation(s) in RCA: 192] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 08/27/2015] [Indexed: 01/23/2023]
Abstract
At last count, nearly 5000 halogenated natural products have been discovered. In approximately half of these compounds, the carbon atom to which the halogen is bound is sp(3) -hybridized; therefore, there are an enormous number of natural products for which stereocontrolled halogenation must be a critical component of any synthesis strategy. In this Review, we critically discuss the methods and strategies used for stereoselective introduction of halogen atoms in the context of natural product synthesis. Using the successes of the past, we also attempt to identify gaps in our synthesis technology that would aid the synthesis of halogenated natural products, as well as existing methods that have not yet seen application in complex molecule synthesis. The chemistry described herein demonstrates yet again how natural products continue to provide the inspiration for critical advances in chemical synthesis.
Collapse
Affiliation(s)
- Won-jin Chung
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju, South Korea.
| | | |
Collapse
|
50
|
Chung WJ, Vanderwal CD. Stereoselektive Halogenierungen in der Naturstoffsynthese. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201506388] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Won-jin Chung
- Department of Chemistry; Gwangju Institute of Science and Technology; Gwangju Südkorea
| | | |
Collapse
|