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Gao ZX, Wang H, Su AH, Li QY, Liang Z, Zhang YQ, Liu XY, Zhu MZ, Zhang HX, Hou YT, Li X, Sun LR, Li J, Xu ZJ, Lou HX. Asymmetric Synthesis and Biological Evaluation of Platensilin, Platensimycin, Platencin, and Their Analogs via a Bioinspired Skeletal Reconstruction Approach. J Am Chem Soc 2024; 146:18967-18978. [PMID: 38973592 DOI: 10.1021/jacs.4c02256] [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: 07/09/2024]
Abstract
Platensilin, platensimycin, and platencin are potent inhibitors of β-ketoacyl-acyl carrier protein synthase (FabF) in the bacterial and mammalian fatty acid synthesis system, presenting promising drug leads for both antibacterial and antidiabetic therapies. Herein, a bioinspired skeleton reconstruction approach is reported, which enables the unified synthesis of these three natural FabF inhibitors and their skeletally diverse analogs, all stemming from a common ent-pimarane core. The synthesis features a diastereoselective biocatalytic reduction and an intermolecular Diels-Alder reaction to prepare the common ent-pimarane core. From this intermediate, stereoselective Mn-catalyzed hydrogen atom-transfer hydrogenation and subsequent Cu-catalyzed carbenoid C-H insertion afford platensilin. Furthermore, the intramolecular Diels-Alder reaction succeeded by regioselective ring opening of the newly formed cyclopropane enables the construction of the bicyclo[3.2.1]-octane and bicyclo[2.2.2]-octane ring systems of platensimycin and platencin, respectively. This skeletal reconstruction approach of the ent-pimarane core facilitates the preparation of analogs bearing different polycyclic scaffolds. Among these analogs, the previously unexplored cyclopropyl analog 47 exhibits improved antibacterial activity (MIC80 = 0.0625 μg/mL) against S. aureus compared to platensimycin.
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Affiliation(s)
- Zong-Xu Gao
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Hongliang Wang
- School of Pharmaceutical Sciences & Institute of Materia Medica, State Key Laboratory of Advanced Drug Delivery System, Shandong First Medical University & Shandong Academy of Medical Sciences, No. 6699, Qingdao Rd, Jinan 250117, P. R. China
| | - Ai-Hong Su
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Qian-Ying Li
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Zhen Liang
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Yue-Qing Zhang
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Xu-Yuan Liu
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Ming-Zhu Zhu
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Hai-Xia Zhang
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Yue-Tong Hou
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Xin Li
- School of Pharmaceutical Sciences & Institute of Materia Medica, State Key Laboratory of Advanced Drug Delivery System, Shandong First Medical University & Shandong Academy of Medical Sciences, No. 6699, Qingdao Rd, Jinan 250117, P. R. China
| | - Long-Ru Sun
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Jian Li
- Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, No. 429, Zhangheng Rd, Shanghai 200213, P. R. China
| | - Ze-Jun Xu
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
| | - Hong-Xiang Lou
- Department of Natural Products Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, No. 44, Wenhuaxi Rd, Jinan 250012, P. R. China
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Trajkovic M, Ferjancic Z, Saicic RN, Bihelovic F. Enantioselective Synthesis of the Platensimycin Core by Silver(I)‐Promoted Cyclization of Δ 6‐α‐Iodoketone. Chemistry 2019; 25:4340-4344. [DOI: 10.1002/chem.201900497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Milos Trajkovic
- Faculty of ChemistryUniversity of Belgrade Studentski trg 16, POB 51 11158 Belgrade 118 Serbia
| | - Zorana Ferjancic
- Faculty of ChemistryUniversity of Belgrade Studentski trg 16, POB 51 11158 Belgrade 118 Serbia
| | - Radomir N. Saicic
- Faculty of ChemistryUniversity of Belgrade Studentski trg 16, POB 51 11158 Belgrade 118 Serbia
- Serbian Academy of Sciences and Arts Knez Mihailova 35 11000 Belgrade Serbia
| | - Filip Bihelovic
- Faculty of ChemistryUniversity of Belgrade Studentski trg 16, POB 51 11158 Belgrade 118 Serbia
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Brill ZG, Condakes ML, Ting CP, Maimone TJ. Navigating the Chiral Pool in the Total Synthesis of Complex Terpene Natural Products. Chem Rev 2017; 117:11753-11795. [PMID: 28293944 PMCID: PMC5638449 DOI: 10.1021/acs.chemrev.6b00834] [Citation(s) in RCA: 186] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The pool of abundant chiral terpene building blocks (i.e., "chiral pool terpenes") has long served as a starting point for the chemical synthesis of complex natural products, including many terpenes themselves. As inexpensive and versatile starting materials, such compounds continue to influence modern synthetic chemistry. This review highlights 21st century terpene total syntheses which themselves use small, terpene-derived materials as building blocks. An outlook to the future of research in this area is highlighted as well.
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Affiliation(s)
- Zachary G. Brill
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720
| | - Matthew L. Condakes
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720
| | - Chi P. Ting
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720
| | - Thomas J. Maimone
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720
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Subba Reddy BV, Nair PN, Antony A, Srivastava N. Recent Advances in Prins Spirocyclization. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700633] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- B. V. Subba Reddy
- Centre for Semio Chemicals; CSIR - Indian Institute of Chemical Technology; Hyderabad India
| | - Preethi Narayanan Nair
- Centre for Semio Chemicals; CSIR - Indian Institute of Chemical Technology; Hyderabad India
| | - Aneesh Antony
- Centre for Semio Chemicals; CSIR - Indian Institute of Chemical Technology; Hyderabad India
| | - Nikhil Srivastava
- Centre for Semio Chemicals; CSIR - Indian Institute of Chemical Technology; Hyderabad India
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5
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A brief history of antibiotics and select advances in their synthesis. J Antibiot (Tokyo) 2017; 71:153-184. [DOI: 10.1038/ja.2017.62] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 04/17/2017] [Accepted: 04/23/2017] [Indexed: 12/20/2022]
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Han JC, Li CC. Ruthenium-Catalyzed Metathesis Cascade Reactions in Natural Products Synthesis. CHEM REC 2016; 17:499-517. [PMID: 27775863 DOI: 10.1002/tcr.201600110] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 09/12/2016] [Indexed: 12/20/2022]
Abstract
In this account, we provide a brief summary of recent developments in ruthenium-catalyzed metathesis cascade reactions towards the total synthesis of natural products. We also highlight recent progress from our own laboratory regarding the synthesis of securinega alkaloids and humulanolides, which has resulted in the development of novel ruthenium-catalyzed metathesis cascade reactions. Inspired and guided by the pioneering and elegant research conducted in this area, we developed a regio-controlled relay dienyne metathesis cascade reaction and a cyclobutene-promoted RCM/ROM/RCM cascade reaction for the synthesis of securinega alkaloids and humulanolides, respectively.
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Affiliation(s)
- Jing-Chun Han
- Department of Chemistry, South University of Science and Technology of China, Shenzhen, 518055, China
| | - Chuang-Chuang Li
- Department of Chemistry, South University of Science and Technology of China, Shenzhen, 518055, China
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8
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Maertens G, L'Homme C, Canesi S. Total synthesis of natural products using hypervalent iodine reagents. Front Chem 2015; 2:115. [PMID: 25601909 PMCID: PMC4283662 DOI: 10.3389/fchem.2014.00115] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 12/10/2014] [Indexed: 12/16/2022] Open
Abstract
We present a review of natural product syntheses accomplished in our laboratory during the last 5 years. Each synthetic route features a phenol dearomatization promoted by an environmentally benign hypervalent iodine reagent. The dearomatizations demonstrate the "aromatic ring umpolung" concept, and involve stereoselective remodeling of the inert unsaturations of a phenol into a highly functionalized key intermediate that may contain a quaternary carbon center and a prochiral dienone system. Several new oxidative strategies were employed, including transpositions (1,3-alkyl shift and Prins-pinacol), a polycyclization, an ipso rearrangement, and direct nucleophilic additions at the phenol para position. Several alkaloids, heterocyclic compounds, and a polycyclic core have been achieved, including sceletenone (a serotonin reuptake inhibitor), acetylaspidoalbidine (an antitumor agent), fortucine (antiviral and antitumor), erysotramidine (curare-like effect), platensimycin (an antibiotic), and the main core of a kaurane diterpene (immunosuppressive agent and stimulator of apoptosis). These concise and in some cases enantioselective syntheses effectively demonstrate the importance of hypervalent iodine reagents in the total synthesis of bioactive natural products.
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Affiliation(s)
| | | | - Sylvain Canesi
- Laboratoire de Méthodologie et Synthèse de Produits Naturels, Département de Chimie, Université du Québec à MontréalMontréal, QC, Canada
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Jiao ZW, Tu YQ, Zhang Q, Liu WX, Wang SH, Wang M. Formal synthesis of (−)-platensimycin. Org Chem Front 2015. [DOI: 10.1039/c5qo00109a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient formal synthesis of (−)-platensimycin was completed by using a tandem C–H oxidation/C–C coupling (cyclization)/rearrangement as the key step.
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Affiliation(s)
- Zhi-Wei Jiao
- School of Pharmacy & State Key Laboratory of Applied Organic Chemistry Lanzhou University
- Lanzhou
- P. R. China
| | - Yong-Qiang Tu
- School of Pharmacy & State Key Laboratory of Applied Organic Chemistry Lanzhou University
- Lanzhou
- P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering
- Tianjin
| | - Qing Zhang
- School of Pharmacy & State Key Laboratory of Applied Organic Chemistry Lanzhou University
- Lanzhou
- P. R. China
| | - Wen-Xing Liu
- School of Pharmacy & State Key Laboratory of Applied Organic Chemistry Lanzhou University
- Lanzhou
- P. R. China
| | - Shao-Hua Wang
- School of Pharmacy & State Key Laboratory of Applied Organic Chemistry Lanzhou University
- Lanzhou
- P. R. China
| | - Min Wang
- College of Material
- Chemistry and Chemical Engineering
- Hangzhou Normal University
- Hangzhou 310036
- P. R. China
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10
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Eey STC, Lear MJ. Total Synthesis of (−)-Platensimycin by Advancing Oxocarbenium- and Iminium-Mediated Catalytic Methods. Chemistry 2014; 20:11556-73. [DOI: 10.1002/chem.201400131] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Indexed: 11/10/2022]
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Zhu L, Zhou C, Yang W, He S, Cheng GJ, Zhang X, Lee CS. Formal Syntheses of (±)-Platensimycin and (±)-Platencin via a Dual-Mode Lewis Acid Induced Cascade Cyclization Approach. J Org Chem 2013; 78:7912-29. [DOI: 10.1021/jo401105q] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Lizhi Zhu
- Laboratory of Chemical Genomics,
School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University
Town, Xili, Shenzhen 518055, China
| | - Congshan Zhou
- Laboratory of Chemical Genomics,
School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University
Town, Xili, Shenzhen 518055, China
- College of Chemistry and Chemical
Engineering, Hunan Institute of Science and Technology, Yueyang 414006, China
| | - Wei Yang
- Laboratory of Chemical Genomics,
School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University
Town, Xili, Shenzhen 518055, China
| | - Shuzhong He
- Laboratory of Chemical Genomics,
School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University
Town, Xili, Shenzhen 518055, China
| | - Gui-Juan Cheng
- Laboratory of Chemical Genomics,
School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University
Town, Xili, Shenzhen 518055, China
| | - Xinhao Zhang
- Laboratory of Chemical Genomics,
School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University
Town, Xili, Shenzhen 518055, China
| | - Chi-Sing Lee
- Laboratory of Chemical Genomics,
School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University
Town, Xili, Shenzhen 518055, China
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13
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Zhu L, Han Y, Du G, Lee CS. A Bifunctional Lewis Acid Induced Cascade Cyclization to the Tricyclic Core of ent-Kaurenoids and Its Application to the Formal Synthesis of (±)-Platensimycin. Org Lett 2013; 15:524-7. [DOI: 10.1021/ol3033412] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Lizhi Zhu
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University Town, Xili, Shenzhen 518055, China
| | - Yejian Han
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University Town, Xili, Shenzhen 518055, China
| | - Guangyan Du
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University Town, Xili, Shenzhen 518055, China
| | - Chi-Sing Lee
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen University Town, Xili, Shenzhen 518055, China
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14
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Nicolaou KC, Hale CRH, Nilewski C, Ioannidou HA. Constructing molecular complexity and diversity: total synthesis of natural products of biological and medicinal importance. Chem Soc Rev 2012; 41:5185-238. [PMID: 22743704 PMCID: PMC3426871 DOI: 10.1039/c2cs35116a] [Citation(s) in RCA: 159] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The advent of organic synthesis and the understanding of the molecule as they occurred in the nineteenth century and were refined in the twentieth century constitute two of the most profound scientific developments of all time. These discoveries set in motion a revolution that shaped the landscape of the molecular sciences and changed the world. Organic synthesis played a major role in this revolution through its ability to construct the molecules of the living world and others like them whose primary element is carbon. Although the early beginnings of organic synthesis came about serendipitously, organic chemists quickly recognized its potential and moved decisively to advance and exploit it in myriad ways for the benefit of mankind. Indeed, from the early days of the synthesis of urea and the construction of the first carbon-carbon bond, the art of organic synthesis improved to impressively high levels of sophistication. Through its practice, today chemists can synthesize organic molecules--natural and designed--of all types of structural motifs and for all intents and purposes. The endeavor of constructing natural products--the organic molecules of nature--is justly called both a creative art and an exact science. Often called simply total synthesis, the replication of nature's molecules in the laboratory reflects and symbolizes the state of the art of synthesis in general. In the last few decades a surge in total synthesis endeavors around the world led to a remarkable collection of achievements that covers a wide ranging landscape of molecular complexity and diversity. In this article, we present highlights of some of our contributions in the field of total synthesis of natural products of biological and medicinal importance. For perspective, we also provide a listing of selected examples of additional natural products synthesized in other laboratories around the world over the last few years.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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Waser M. Iminium Catalysis. ASYMMETRIC ORGANOCATALYSIS IN NATURAL PRODUCT SYNTHESES 2012:45-68. [DOI: 10.1007/978-3-7091-1163-5_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Beaulieu MA, Guérard KC, Maertens G, Sabot C, Canesi S. Oxidative Prins-Pinacol Tandem Process Mediated by a Hypervalent Iodine Reagent: Scope, Limitations, and Applications. J Org Chem 2011; 76:9460-71. [DOI: 10.1021/jo2019027] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marc-André Beaulieu
- Laboratoire de Méthodologie et Synthèse
de Produits Naturels, Université du Québec à Montréal, C.P. 8888, Succ. Centre-Ville,
Montréal, H3C 3P8 Québec, Canada
| | - Kimiaka C. Guérard
- Laboratoire de Méthodologie et Synthèse
de Produits Naturels, Université du Québec à Montréal, C.P. 8888, Succ. Centre-Ville,
Montréal, H3C 3P8 Québec, Canada
| | - Gaëtan Maertens
- Laboratoire de Méthodologie et Synthèse
de Produits Naturels, Université du Québec à Montréal, C.P. 8888, Succ. Centre-Ville,
Montréal, H3C 3P8 Québec, Canada
| | - Cyrille Sabot
- Laboratoire de Méthodologie et Synthèse
de Produits Naturels, Université du Québec à Montréal, C.P. 8888, Succ. Centre-Ville,
Montréal, H3C 3P8 Québec, Canada
| | - Sylvain Canesi
- Laboratoire de Méthodologie et Synthèse
de Produits Naturels, Université du Québec à Montréal, C.P. 8888, Succ. Centre-Ville,
Montréal, H3C 3P8 Québec, Canada
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Oblak EZ, Wright DL. Highly Substituted Oxabicyclic Derivatives from Furan: Synthesis of (±)-Platensimycin. Org Lett 2011; 13:2263-5. [DOI: 10.1021/ol2005775] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- E. Zachary Oblak
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Dennis L. Wright
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269, United States
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Yoshida JI, Kim H, Nagaki A. Green and sustainable chemical synthesis using flow microreactors. CHEMSUSCHEM 2011; 4:331-40. [PMID: 21394921 DOI: 10.1002/cssc.201000271] [Citation(s) in RCA: 298] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Indexed: 05/12/2023]
Abstract
Several features that allow flow microreactors contribute to green and sustainable chemical synthesis are presented: (1) For extremely fast reactions, kinetics often cannot be used because of the lack of homogeneity of the reaction environment when they are conducted in batch macroreactors. Better controllability, by virtue of fast mixing based on short diffusion paths in microreactors, however, leads to a higher selectivity of the products, based on kinetics considerations. Therefore, less waste is produced. (2) Reactions involving highly unstable intermediates usually require very low temperatures when they are conducted in macrobatch reactors. By virtue of short residence times, flow microreactors enable performing such reactions at ambient temperatures, avoiding cryogenic conditions and minimizing the energy required for cooling. (3) By virtue of the precise residence time control, flow microreactors allow to avoid the use of auxiliary substances such as protecting groups, enabling highly atom- and step-economical straightforward syntheses. The development of several test plants based on microreaction technology has proved that flow microreactor synthesis can be applied to the green and sustainable production of chemical substances on industrial scales. (4) Microreactor technology enables on-demand and on-site synthesis, which leads to less energy for transportation and easy recycling of substances.
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Affiliation(s)
- Jun-ichi Yoshida
- Department of Synthetic and Biological Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan.
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Wang J, Sintim HO. Dialkylamino-2,4-dihydroxybenzoic Acids as Easily Synthesized Analogues of Platensimycin and Platencin with Comparable Antibacterial Properties. Chemistry 2011; 17:3352-7. [DOI: 10.1002/chem.201002410] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 12/14/2010] [Indexed: 11/08/2022]
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Zheng JC, Yun SY, Sun C, Lee NK, Lee D. Selectivity Control in Alkylidene Carbene-Mediated C−H Insertion and Allene Formation. J Org Chem 2011; 76:1086-99. [PMID: 21244086 DOI: 10.1021/jo102180f] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Jun-Cheng Zheng
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Sang Young Yun
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Chunrui Sun
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Nam-Kyu Lee
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Daesung Lee
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
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Hirai S, Nakada M. Enantioselective divergent approaches to both (−)-platensimycin and (−)-platencin. Tetrahedron 2011. [DOI: 10.1016/j.tet.2010.10.076] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Saleem M, Hussain H, Ahmed I, van Ree T, Krohn K. Platensimycin and its relatives: A recent story in the struggle to develop new naturally derived antibiotics. Nat Prod Rep 2011; 28:1534-79. [DOI: 10.1039/c1np00010a] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Palanichamy K, Subrahmanyam AV, Kaliappan KP. A radical cyclization approach to the formal total syntheses of platencin. Org Biomol Chem 2011; 9:7877-86. [DOI: 10.1039/c1ob06155k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Tiefenbacher K, Gollner A, Mulzer J. Syntheses and antibacterial properties of iso-platencin, Cl-iso-platencin and Cl-platencin: identification of a new lead structure. Chemistry 2010; 16:9616-22. [PMID: 20486112 DOI: 10.1002/chem.201000706] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Platencin is a novel antibiotic which is active against multiresistant pathogens. We describe efficient syntheses of three platencin analogues of varying activities which allow further conclusions about the pharmacophoric part of the molecule. The unnatural antibiotic iso-platencin, which is about as active as natural platencin, but much more selective, was identified as a new lead structure.
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Affiliation(s)
- Konrad Tiefenbacher
- University of Vienna, Institute of Organic Chemistry, Währingerstrasse 38, 1090 Wien, Austria
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Eey STC, Lear MJ. A Bismuth(III)-Catalyzed Friedel−Crafts Cyclization and Stereocontrolled Organocatalytic Approach to (−)-Platensimycin. Org Lett 2010; 12:5510-3. [DOI: 10.1021/ol102390t] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Stanley T.-C. Eey
- Department of Chemistry, Faculty of Science, and Medicinal Chemistry Program of the Life Sciences Institute, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Martin J. Lear
- Department of Chemistry, Faculty of Science, and Medicinal Chemistry Program of the Life Sciences Institute, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
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26
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Hirai S, Nakada M. An enantioselective approach to (−)-platencin via catalytic asymmetric intramolecular cyclopropanation. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.07.088] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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27
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Beaulieu MA, Sabot C, Achache N, Guérard KC, Canesi S. An Oxidative Prins-Pinacol Tandem Process and its Application to the synthesis of (−)-Platensimycin. Chemistry 2010; 16:11224-8. [DOI: 10.1002/chem.201001813] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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28
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Nagaki A, Kim H, Moriwaki Y, Matsuo C, Yoshida JI. A Flow Microreactor System Enables Organolithium Reactions without Protecting Alkoxycarbonyl Groups. Chemistry 2010; 16:11167-77. [DOI: 10.1002/chem.201000876] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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29
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Tiefenbacher K, Tröndlin L, Mulzer J, Pfaltz A. An expeditious asymmetric formal synthesis of the antibiotic platensimycin. Tetrahedron 2010. [DOI: 10.1016/j.tet.2010.04.098] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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30
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Palanichamy K, Kaliappan KP. Discovery and syntheses of "superbug challengers"-platensimycin and platencin. Chem Asian J 2010; 5:668-703. [PMID: 20209576 DOI: 10.1002/asia.200900423] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Bacteria have developed resistance to almost all existing antibiotics known today and this has been a major issue over the last few decades. The search for a new class of antibiotics with a new mode of action to fight these multiply-drug-resistant strains, or "superbugs", allowed a team of scientists at Merck to discover two novel antibiotics, platensimycin and platencin using advanced screening strategies, as inhibitors of bacterial fatty acid biosynthesis, which is essential for the survival of bacteria. Though both these antibiotics are structurally related, they work by slightly different mechanisms and target different enzymes conserved in the bacterial fatty acid biosynthesis. This Focus Review summarizes the synthetic and biological aspects of these natural products and their analogues and congeners.
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Affiliation(s)
- Kalanidhi Palanichamy
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, India
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31
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Zhang C, Ondeyka J, Dietrich L, Gailliot FP, Hesse M, Lester M, Dorso K, Motyl M, Ha SN, Wang J, Singh SB. Isolation, structure and biological activities of platencin A2–A4 from Streptomyces platensis. Bioorg Med Chem 2010; 18:2602-10. [DOI: 10.1016/j.bmc.2010.02.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Revised: 02/14/2010] [Accepted: 02/18/2010] [Indexed: 11/26/2022]
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32
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Jang KP, Kim CH, Na SW, Jang DS, Kim H, Kang H, Lee E. 7-Phenylplatensimycin and 11-methyl-7-phenylplatensimycin: more potent analogs of platensimycin. Bioorg Med Chem Lett 2010; 20:2156-8. [PMID: 20207542 DOI: 10.1016/j.bmcl.2010.02.037] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 02/02/2010] [Accepted: 02/09/2010] [Indexed: 10/19/2022]
Abstract
Carbonyl ylide cycloaddition strategy was employed in the synthesis of platensimycin analogs. 7-Phenylplatensimycin and 11-methyl-7-phenylplatensimycin are more potent analogs of platensimycin.
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Affiliation(s)
- Ki Po Jang
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 151-747, Republic of Korea
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33
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La Clair JJ. Natural product mode of action (MOA) studies: a link between natural and synthetic worlds. Nat Prod Rep 2010; 27:969-95. [DOI: 10.1039/b909989c] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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34
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Singh V, Sahu BC, Bansal V, Mobin SM. Intramolecular cycloaddition in 6,6-spiroepoxycyclohexa-2,4-dienone: simple aromatics to (±)-Platencin. Org Biomol Chem 2010; 8:4472-81. [DOI: 10.1039/c004316h] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Chen P, Cao L, Li C. Protecting-group-free total synthesis of (+/-)-subincanadine F. J Org Chem 2009; 74:7533-5. [PMID: 19778081 DOI: 10.1021/jo901444e] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
With chemoselective Dieckmann condensation as the key step, the protective-group-free total synthesis of (+/-)-subincanadine F was accomplished in 7 steps from the commercially available tryptamine in 33% overall yield.
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Affiliation(s)
- Pinhong Chen
- Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People's republic of China
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36
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Nicolaou KC, Li A, Edmonds DJ, Tria GS, Ellery SP. Total synthesis of platensimycin and related natural products. J Am Chem Soc 2009; 131:16905-18. [PMID: 19874023 PMCID: PMC2783699 DOI: 10.1021/ja9068003] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Platensimycin is the flagship member of a new and growing class of antibiotics with promising antibacterial properties against drug-resistant bacteria. The total syntheses of platensimycin and its congeners, platensimycins B(1) and B(3), platensic acid, methyl platensinoate, platensimide A, homoplatensimide A, and homoplatensimide A methyl ester, are described. The convergent strategy developed toward these target molecules involved construction of their cage-like core followed by attachment of the various side chains through amide bond formation. In addition to a racemic synthesis, two asymmetric routes to the core structure are described: one exploiting a rhodium-catalyzed asymmetric cycloisomerization, and another employing a hypervalent iodine-mediated de-aromatizing cyclization of an enantiopure substrate. The final two bonds of the core structure were forged through a samarium diiodide-mediated ketyl radical cyclization and an acid-catalyzed etherification. The rhodium-catalyzed asymmetric reaction involving a terminal acetylene was developed as a general method for the asymmetric cycloisomerization of terminal enynes.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
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37
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Nicolaou KC, Tria GS, Edmonds DJ, Kar M. Total syntheses of (+/-)-platencin and (-)-platencin. J Am Chem Soc 2009; 131:15909-17. [PMID: 19824676 PMCID: PMC2783895 DOI: 10.1021/ja906801g] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The secondary metabolites platensimycin and platencin, isolated from the bacterial strain Streptomyces platensis, represent a novel class of natural products exhibiting unique and potent antibacterial activity. Platencin, though structurally similar to platensimycin, has been found to operate through a slightly different mechanism of action involving the dual inhibition of lipid elongation enzymes FabF and FabH. Both natural products exhibit strong, broad-spectrum, gram-positive antibacterial activity to key antibiotic resistant strains, including methicillin-resistant Staphylococcus aureus, vancomycin-intermediate S. aureus, and vancomycin-resistant Enterococcus faecium. Described herein are our synthetic efforts toward platencin, culminating in both racemic and asymmetric preparation of the natural product. The syntheses demonstrate the power of the cobalt-catalyzed asymmetric Diels-Alder reaction and the one-pot reductive rearrangement of [3.2.1] bicyclic ketones to [2.2.2] bicyclic olefins.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
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38
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McGrath N, Bartlett E, Sittihan S, Njardarson J. A Concise Ring-Expansion Route to the Compact Core of Platensimycin. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200903347] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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39
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Ghosh A, Xi K. A Symmetry-Based Concise Formal Synthesis of Platencin, a Novel Lead against “Superbugs”. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200902338] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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40
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A synthesis of sulfonamide analogs of platensimycin employing a palladium-mediated carbonylation strategy. Tetrahedron Lett 2009. [DOI: 10.1016/j.tetlet.2009.04.105] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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41
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Isoplatensimycin: Synthesis and biological evaluation. Bioorg Med Chem Lett 2009; 19:4601-2. [PMID: 19604693 DOI: 10.1016/j.bmcl.2009.06.092] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 06/05/2009] [Accepted: 06/24/2009] [Indexed: 11/24/2022]
Abstract
Isoplatensimycin, a novel analog of platensimycin, was synthesized via intramolecular dipolar cycloaddition of a carbonyl ylide. Isoplatensimycin showed little activities against strains of Staphylococcus aureus, but exhibited activities against some vancomycin-resistant enteroccoci.
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42
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43
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Yun SY, Zheng JC, Lee D. Stereoelectronic Effect for the Selectivity in C−H Insertion of Alkylidene Carbenes and Its Application to the Synthesis of Platensimycin. J Am Chem Soc 2009; 131:8413-5. [PMID: 19473019 DOI: 10.1021/ja903526g] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sang Young Yun
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607-7061
| | - Jun-Cheng Zheng
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607-7061
| | - Daesung Lee
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607-7061
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44
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Matsuo JI, Kawano M, Takeuchi K, Tanaka H, Ishibashi H. Asymmetric synthesis of 2-alkyl-4-hydroxycyclohex-2-en-1-ones by scandium(III) triflate-catalyzed fragmentation of 2-alkyl-3-iodo-1-oxocyclohexan-2,4-carbolactones. Tetrahedron Lett 2009. [DOI: 10.1016/j.tetlet.2009.02.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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45
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Wang J, Lee V, Sintim H. Efforts towards the Identification of Simpler Platensimycin Analogues-The Total Synthesis of Oxazinidinyl Platensimycin. Chemistry 2009; 15:2747-50. [DOI: 10.1002/chem.200802568] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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46
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Affiliation(s)
- Konrad Tiefenbacher
- Institute of Organic Chemistry, University of Vienna, Währingerstrasse 38, 1090 Vienna, Austria
| | - Johann Mulzer
- Institute of Organic Chemistry, University of Vienna, Währingerstrasse 38, 1090 Vienna, Austria
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47
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Shen HC, Ding FX, Singh SB, Parthasarathy G, Soisson SM, Ha SN, Chen X, Kodali S, Wang J, Dorso K, Tata JR, Hammond ML, Maccoss M, Colletti SL. Synthesis and biological evaluation of platensimycin analogs. Bioorg Med Chem Lett 2009; 19:1623-7. [PMID: 19233644 DOI: 10.1016/j.bmcl.2009.02.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Revised: 01/29/2009] [Accepted: 02/02/2009] [Indexed: 10/21/2022]
Abstract
Platensimycin (1) displays antibacterial activity due to its inhibition of the elongation condensing enzyme (FabF), a novel mode of action that could potentially lead to a breakthrough in developing a new generation of antibiotics. The medicinal chemistry efforts were focused on the modification of the enone moiety of platensimycin and several analogs showed significant activity against FabF and possess antibacterial activity.
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Affiliation(s)
- Hong C Shen
- Departments of Medicinal Chemistry, Merck Research Laboratories, PO Box 2000, Rahway, NJ 07065-0900, USA
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48
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Abstract
An enantioselective synthesis of platensimycin, a novel antibiotic natural product that inhibits bacterial beta-ketoacyl-(acyl-carrier-protein) synthase (FabF), is described. Our synthetic strategy for the construction of the oxatetracyclic core involved an intramolecular Diels-Alder reaction. Our preliminary studies provided a complex tetracyclic product by first undergoing an interesting 1,5-hydride shift followed by a Diels-Alder reaction. Further optimization of the diene's electronic properties, by incorporation of a methoxy group, led to the oxatetracyclic core of platensimycin. The three required chiral centers, including two all-carbon quaternary chiral centers, were built in the intramolecular Diels-Alder step. The synthesis utilized natural (+)-carvone as the key chiral starting material, which determined the stereochemistry of the final product. The synthesis also featured an efficient Petasis olefination, a hydroboration sequence, a Gais's asymmetric Horner-Wadsworth-Emmons reaction, and a mercury salt catalyzed enol ether isomerization.
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Affiliation(s)
- Arun K Ghosh
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
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49
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Nicolaou K, Chen J, Edmonds D, Estrada A. Fortschritte in der Chemie und Biologie natürlicher Antibiotika. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200801695] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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50
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McGrath NA, Bartlett ES, Sittihan S, Njardarson JT. A concise ring-expansion route to the compact core of platensimycin. Angew Chem Int Ed Engl 2009; 48:8543-6. [PMID: 19798708 PMCID: PMC3107035 DOI: 10.1002/anie.200903347] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Nicholas A. McGrath
- Department of Chemistry and Chemical Biology, Baker Laboratory Cornell University, Ithaca, NY 14853-1301 (USA)
| | - Emily S. Bartlett
- Department of Chemistry and Chemical Biology, Baker Laboratory Cornell University, Ithaca, NY 14853-1301 (USA)
| | - Satapanawat Sittihan
- Department of Chemistry and Chemical Biology, Baker Laboratory Cornell University, Ithaca, NY 14853-1301 (USA)
| | - Jon T. Njardarson
- Department of Chemistry and Chemical Biology, Baker Laboratory Cornell University, Ithaca, NY 14853-1301 (USA)
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