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Wang RB, Ma SG, Jamieson CS, Gao RM, Liu YB, Li Y, Wang XJ, Li YH, Houk KN, Qu J, Yu SS. Library construction of stereochemically diverse isomers of spirooliganin: their total synthesis and antiviral activity. Chem Sci 2021; 12:7003-7011. [PMID: 34123328 PMCID: PMC8153216 DOI: 10.1039/d1sc01277k] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The construction of libraries of stereoisomers of natural products serves as an important approach to investigating the correlation between the stereostructure and biological activity. However, the total synthesis and isomerzation of polycyclic scaffolds with multiple chrial centers are rare. Spirooliganin (1), a new skeleton natural product isolated from the plant Illicium oligandrum, was structurally characterized by comprehensive analysis of NMR spectroscopic data and ECD which revealed an unprecedented 5-6-6-6-7 polycyclic framework with six chiral centers. Here we report a 17-step total synthesis to prepare a library of stereochemically diverse isomers of spirooliganin, including 16 diastereoisomers and 16 regioisomers. In addition to a regioselective hetero-Diels-Alder cycloaddition, the synthetic strategy involves a photo-induced stereoselective Diels-Alder reaction, which gives only the abnormal trans-fused product as rationalized by density functional theory calculations. Preliminary biological evaluation showed that spirooliganin and regioisomers 39 exhibited potent inhibition of Coxsackievirus B3. It also revealed the pharmacophore effect of the D-ring (16R,18R,24R, and 26R) for their antiviral activities.
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Affiliation(s)
- Ru-Bing Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College No.1 Xian Nong Tan Street Beijing 100050 People's Republic of China
| | - Shuang-Gang Ma
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College No.1 Xian Nong Tan Street Beijing 100050 People's Republic of China
| | - Cooper S Jamieson
- Department of Chemistry and Biochemistry, University of California Los Angeles California 90095 USA
| | - Rong-Mei Gao
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College No. 1 Tian Tan Xi Li Beijing 100050 People's Republic of China
| | - Yun-Bao Liu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College No.1 Xian Nong Tan Street Beijing 100050 People's Republic of China
| | - Yong Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College No.1 Xian Nong Tan Street Beijing 100050 People's Republic of China
| | - Xiao-Jing Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College No.1 Xian Nong Tan Street Beijing 100050 People's Republic of China
| | - Yu-Huan Li
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College No. 1 Tian Tan Xi Li Beijing 100050 People's Republic of China
| | - Kendall N Houk
- Department of Chemistry and Biochemistry, University of California Los Angeles California 90095 USA
| | - Jing Qu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College No.1 Xian Nong Tan Street Beijing 100050 People's Republic of China
| | - Shi-Shan Yu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College No.1 Xian Nong Tan Street Beijing 100050 People's Republic of China
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Turkyilmaz S, Wilcox CS. Asymmetric solution-phase mixture aldol reaction using oligomeric ethylene glycol tagged chiral oxazolidinones. Tetrahedron Lett 2017; 58:2031-2033. [PMID: 29056780 PMCID: PMC5646709 DOI: 10.1016/j.tetlet.2017.04.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Sorting tags are oligomeric structures that can be used as protecting groups or chiral auxiliaries enabling solution-phase mixture syntheses of multiple tagged compounds in one pot and allowing for facile and predictable chromatographic separation of products at the end of synthetic sequences. Perfluorinated hydrocarbon and oligomeric ethylene glycol (OEG) derivatives are known classes of sorting tags. Herein we describe the preparation of OEGylated chiral oxazolidinones and their use in asymmetric solution-phase mixture aldol reactions. Through the use of such oxazolidinones based on tyrosine four different individually tagged aldol adducts were obtained as a mixture, chromatographically demixed, detagged, and it was shown that these processes gave the desired aldol products in good yield and enantioselectivity.
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Affiliation(s)
- Serhan Turkyilmaz
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Istanbul University, 34116 Beyazit, Istanbul, Turkey
| | - Craig S. Wilcox
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
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3
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Florence GJ, Morris JC, Murray RG, Vanga RR, Osler JD, Smith TK. Total synthesis, stereochemical assignment, and biological activity of chamuvarinin and structural analogues. Chemistry 2013; 19:8309-20. [PMID: 23630031 DOI: 10.1002/chem.201204527] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 03/14/2013] [Indexed: 11/06/2022]
Abstract
A highly stereocontrolled synthesis of (+)-chamuvarinin has been completed in 1.5% overall yield over 20 steps. The key fragment coupling reactions were the addition of alkyne 8 to aldehyde 7 (under Felkin-Anh control), followed by the two step activation/cyclization to close the C20-C23 2,5-cis-substituted tetrahydrofuran ring and a Julia-Kocienski olefination at C8-C9 to introduce the terminal butenolide. The inherent flexibility of our coupling strategy led to a streamlined synthesis with 17 steps in the longest sequence (2.2% overall yield), in which the key bond couplings are reversed. In addition, a series of structural analogues of chamuvarinin have been prepared and screened for activity against HeLa cancer cell lines and both the bloodstream and insect forms of Trypanosoma brucei, the parasitic agent responsible for African sleeping sickness.
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Affiliation(s)
- Gordon J Florence
- EaStCHEM School of Chemistry, Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK.
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4
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Moretti JD, Wang X, Curran DP. Minimal fluorous tagging strategy that enables the synthesis of the complete stereoisomer library of SCH725674 macrolactones. J Am Chem Soc 2012; 134:7963-70. [PMID: 22515682 DOI: 10.1021/ja302260d] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Four mixtures of four fluorous-tagged quasiisomers have been synthesized, demixed, and detagged to make all 16 stereoisomers of the macrocyclic lactone natural product Sch725674. A new bare-minimum tagging pattern needs only two tags--one fluorous and one nonfluorous--to encode four isomers. The structure of Sch725674 is assigned as (5R,6S,8R,14R,E)-5,6,8-trihydroxy-14-pentyloxacyclotetradec-3-en-2-one. Various comparisons of spectra of 32 lactones (16 with tags, 16 without) and 16 ester precursors (8 with tags, 8 without) provide insights into when and why related compounds have the same or different spectra.
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Affiliation(s)
- Jared D Moretti
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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5
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Total synthesis of cucurbitoside-like phenolic glycosides by double fluorous and acyl mixture synthesis. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.08.087] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Florence GJ, Morris JC, Murray RG, Osler JD, Reddy VR, Smith TK. Synthesis and stereochemical assignment of (+)-chamuvarinin. Org Lett 2010; 13:514-7. [PMID: 21174397 PMCID: PMC3031177 DOI: 10.1021/ol1028699] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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A stereocontrolled total synthesis of (+)-chamuvarinin, isolated from the root extract of Uvaria Chamae, utilizes a convergent modular strategy to construct the adjacently linked C15−C28 ether array, followed by a late-stage Julia−Kocienski olefination to append the butenolide motif. This constitutes the first total synthesis of (+)-chamuvarinin, defining the relative and absolute configuration of this unique annonaceous acetogenin.
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Affiliation(s)
- Gordon J Florence
- School of Chemistry and Centre for Biomolecular Sciences, University of St. Andrews, North Haugh, St. Andrews, KY16 9ST, UK.
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Yajima T, Tonoi T, Nagano H, Tomita Y, Mikami K. Direct Racemic Mixture Synthesis of Fluorinated Amino Acids by Perfluoroalkyl Radical Addition to Dehydroamino Acids Terminated by Asymmetric Protonation. European J Org Chem 2010. [DOI: 10.1002/ejoc.201000017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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8
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Lu Y, Geib SJ, Damodaran K, Sui B, Zhang Z, Curran DP, Zhang W. Fluorous diastereomeric mixture synthesis (FDMS) of hydantoin-fused hexahydrochromeno[4,3-b]pyrroles. Chem Commun (Camb) 2010; 46:7578-80. [DOI: 10.1039/c0cc01967d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Nandy JP, Prakesch M, Khadem S, Reddy PT, Sharma U, Arya P. Advances in Solution- and Solid-Phase Synthesis toward the Generation of Natural Product-like Libraries. Chem Rev 2009; 109:1999-2060. [DOI: 10.1021/cr800188v] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Jyoti P. Nandy
- Ontario Institute for Cancer Research, MaRS Centre, South Tower, 101 College Street, Toronto, Ontario M5G 1L7, Canada, Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada, and Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Michael Prakesch
- Ontario Institute for Cancer Research, MaRS Centre, South Tower, 101 College Street, Toronto, Ontario M5G 1L7, Canada, Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada, and Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Shahriar Khadem
- Ontario Institute for Cancer Research, MaRS Centre, South Tower, 101 College Street, Toronto, Ontario M5G 1L7, Canada, Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada, and Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - P. Thirupathi Reddy
- Ontario Institute for Cancer Research, MaRS Centre, South Tower, 101 College Street, Toronto, Ontario M5G 1L7, Canada, Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada, and Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Utpal Sharma
- Ontario Institute for Cancer Research, MaRS Centre, South Tower, 101 College Street, Toronto, Ontario M5G 1L7, Canada, Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada, and Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Prabhat Arya
- Ontario Institute for Cancer Research, MaRS Centre, South Tower, 101 College Street, Toronto, Ontario M5G 1L7, Canada, Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada, and Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
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10
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Affiliation(s)
- Wei Zhang
- Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Boulevard, Boston, Massachusetts 02125
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11
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Park G, Ko KS, Zakharova A, Pohl NL. Mono- Vs. Di-flourous tagged Glucosamines for Iterative Oligosaccharide Synthesis. J Fluor Chem 2008; 129:978-982. [PMID: 19802334 DOI: 10.1016/j.jfluchem.2008.05.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Fluorous-tagged protecting groups are attractive tools for elongating carbohydrate chains in oligosaccharide synthesis. To eliminate the accumulation of failed sequences during automated oligosaccharide synthesis conditions, an additional C(8)F(17) ester derived protecting group was attached to the glycosyl donor to better retain the desired doubly-tagged glycosylation product on fluorous solid phase extraction (FSPE) cartridges. Initial studies show that the double-fluorous-tagging strategy offers a robust enough separation using a commercial FSPE cartridge using simple gravity filtration to separate the desired product from the singly-fluorous-tagged starting materials and their decomposition products. In addition, removal of the fluorous acetate and its byproducts after sodium methoxide treatment and neutralization required only dissolution of the desired sugar in toluene and subsequent removal of the toluene layer from the denser fluorous byproducts.
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Affiliation(s)
- Gisun Park
- 2756 Gilman, Department of Chemistry and the Plant Sciences Institute, Iowa State University, Ames, IA 50011 USA
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12
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Abstract
The article summarizes a lecture presented at the American Chemical Society Symposium for the 2008 Award for Creative Work in Fluorine Chemistry on April 7, 2008. A high level, historical overview of work in the fluorous field at the University of Pittsburgh is presented.
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Affiliation(s)
- Dennis P Curran
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
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13
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Abstract
The affinity fluorous interaction between fluorous tagged small molecules and a fluoroalkyl modified glass surface was shown to facilitate the detection of protein-ligand binding interactions in the fabrication and screening of small molecule microarrays.
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Affiliation(s)
- Rebecca L Nicholson
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UKCB2 1EW
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Hattori Y, Kimura Y, Moroda A, Konno H, Abe M, Miyoshi H, Goto T, Makabe H. Synthesis of Murisolin, (15R, 16R, 19R, 20S)-Murisolin A, and (15R, 16R, 19S, 20S)-16,19-cis-Murisolin and Their Inhibitory Action with Bovine Heart Mitochondrial Complex I. Chem Asian J 2006; 1:894-904. [PMID: 17441133 DOI: 10.1002/asia.200600261] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The asymmetric total synthesis of murisolin, (15R, 16R, 19R, 20S)-murisolin A, and (15R, 16R, 19S, 20S)-16,19-cis-murisolin was performed by using an epoxy alcohol as a versatile chiral building block for synthesizing the stereoisomers of mono-THF annonaceous acetogenins. The inhibitory activity of these murisolin compounds was examined with bovine heart mitochondrial complex I, and they showed almost the same activity.
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Affiliation(s)
- Yasunao Hattori
- Interdisciplinary Graduate School of Science and Technology, Shinshu University, 8304 Minami-Minowa, Kamiina, Nagano 399-4598, Japan
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Szabó D, Mohl J, Bálint AM, Bodor A, Rábai J. Novel generation ponytails in fluorous chemistry: Syntheses of primary, secondary, and tertiary (nonafluoro-tert-butyloxy)ethyl amines. J Fluor Chem 2006. [DOI: 10.1016/j.jfluchem.2006.06.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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16
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Yang F, Newsome JJ, Curran DP. Structure Assignment of Lagunapyrone B by Fluorous Mixture Synthesis of Four Candidate Stereoisomers. J Am Chem Soc 2006; 128:14200-5. [PMID: 17061905 DOI: 10.1021/ja064812s] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Techniques of fluorous mixture synthesis have been used to make four candidate stereoisomers for the natural product lagunapyrone B. A quasiracemic mixture of vinyl iodides whose component configurations at C19-21 were encoded by fluorous silyl groups was fused to a central fragment by a Negishi coupling. A separate quasiracemic mixture of pyrone fragments whose component configurations at C6,7 were also encoded by fluorous silyl groups was synthesized and demixed. Stille coupling of the resulting pure quasienantiomers with the quasiracemic mixture provided two quasi-diastereomeric samples, which were demixed and detagged to provide all four lagunapyrone B stereoisomers. Lagunapyrone was assigned the 6R,7S,19S,20S,21R configuration by comparison of optical rotations.
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Affiliation(s)
- Fanglong Yang
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
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17
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El Bakkari M, Vincent JM. Pyridyl Tags as Phase Labels in Organic Synthesis: Fluorous and Non-Fluorous Approaches. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/qsar.200640055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Curran DP, Zhang Q, Richard C, Lu H, Gudipati V, Wilcox CS. Total Synthesis of a 28-Member Stereoisomer Library of Murisolins. J Am Chem Soc 2006; 128:9561-73. [PMID: 16848495 DOI: 10.1021/ja061801q] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Total syntheses of two 16-member libraries of murisolin isomers are reported. In the first library, fluorous PMB (p-methoxybenzyl) groups encode configurations, and four mixtures of four dihydroxy-tetrahydrofurans are prepared by Shi epoxidation followed (optionally) by Mitsunobu reaction. The mixtures are coupled by Kocienski-Julia reaction with a single hydroxybutenolide followed by hydrogenation. Demixing and detagging provide the 16 pure stereoisomers. In the second synthesis, a single mixture of four fluorous-tagged dihydroxy-tetrahydrofurans is coupled with a four-compound mixture of hydroxybutenolides that bear derivatives of DMB (dimethoxybenzyl) groups with oligoethylene glycol (OEG) units that encode the configurations at C4 and C34. The 16-compound mixture is subjected to hydrogenation, double demixing, and detagging to provide the 16 isomerically pure murisolins. Twelve of these isomers are new, while four match samples from the first library.
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Affiliation(s)
- Dennis P Curran
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
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Curran DP, Moura-Letts G, Pohlman M. Solution-Phase Mixture Synthesis with Fluorous Tagging En Route: Total Synthesis of an Eight-Member Stereoisomer Library of Passifloricins. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200600041] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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20
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Curran DP, Moura-Letts G, Pohlman M. Solution-Phase Mixture Synthesis with Fluorous Tagging En Route: Total Synthesis of an Eight-Member Stereoisomer Library of Passifloricins. Angew Chem Int Ed Engl 2006; 45:2423-6. [PMID: 16526090 DOI: 10.1002/anie.200600041] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dennis P Curran
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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Gudipati V, Curran DP, Wilcox CS. Solution-Phase Parallel Synthesis with Oligoethylene Glycol Sorting Tags. Preparation of All Four Stereoisomers of the Hydroxybutenolide Fragment of Murisolin and Related Acetogenins. J Org Chem 2006; 71:3599-607. [PMID: 16626147 DOI: 10.1021/jo060217x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The principles of the oligoethylene glycol (OEG) mixture synthesis are illustrated with the synthesis of all four possible stereoisomers of a hydroxybutenolide fragment common to murisolin and many other acetogenins. Modified dimethoxybenzyl groups with varying numbers of OEG units (-CH2CH2O-) are used to protect alcohols and serve as codes for configurations at two stereocenters. The encoded isomers are carried through several steps in a sequence of mixing prior to the reaction and then demixing during the separation to give individual pure products. A new tagging scheme is introduced in which a stereocenter bearing a hydroxy group is given two different tags. These initially redundant tags then serve to encode the configuration of another (untagged) stereocenter by appropriate pairwise reactions of the tagged precursors. The experimental features (reaction, analysis, separation, and characterization) of OEG mixture synthesis are detailed and are compared to and contrasted with those of fluorous mixture synthesis.
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Affiliation(s)
- Venugopal Gudipati
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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