1
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Chang CC, Jan HM, Tseng CJ, Mondal S, Abera AB, Hsieh MY, Yang TC, Muthusamy S, Huang SC, Lin CH, Tony Mong KK. Metabolic Isolation, Stereochemical Determination, and Total Synthesis of Predominant Native Cholesteryl Phosphatidyl-α-glucoside from Carcinogenic Helicobacter pylori. Org Lett 2022; 24:5045-5050. [PMID: 35816729 DOI: 10.1021/acs.orglett.2c01815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report the isolation and stereochemical determination of the predominant native cholesteryl 6-O-phosphatidyl α-glucoside (CPG) from Helicobacter pylori via an integrated biological and chemical strategy. The strategy employed (i) the metabolic isolation of a CPG analogue and (ii) the enzymatic degradation of the analogue to obtain the native lactobacillic acid for the stereochemical determination. The absolute stereochemistry of the acid was found to be 11R and 12S. Using the new stereochemical data, we accomplished the total synthesis of predominant native CPG and other predominant αCG derivatives.
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Affiliation(s)
- Chia-Chen Chang
- Applied Chemistry Department, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu City 300093Taiwan, R.O.C
| | - Hau-Ming Jan
- Institute of Biological Chemistry, Academia Sinica, No.128 Academia Road Section 2, Nan-Kang, Taipei 11529, Taiwan
| | - Chieh-Jen Tseng
- Applied Chemistry Department, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu City 300093Taiwan, R.O.C
| | - Soumik Mondal
- Applied Chemistry Department, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu City 300093Taiwan, R.O.C
| | - Andualem Bahiru Abera
- Institute of Biological Chemistry, Academia Sinica, No.128 Academia Road Section 2, Nan-Kang, Taipei 11529, Taiwan.,Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan.,Graduate Institute of Biotechnology and Biotechnology Center, National Chung-Hsing University, Taichung 40227, Taiwan
| | - Ming-Yen Hsieh
- Institute of Biological Chemistry, Academia Sinica, No.128 Academia Road Section 2, Nan-Kang, Taipei 11529, Taiwan
| | - Tsai-Chen Yang
- Institute of Biological Chemistry, Academia Sinica, No.128 Academia Road Section 2, Nan-Kang, Taipei 11529, Taiwan
| | - Sasikala Muthusamy
- Institute of Biological Chemistry, Academia Sinica, No.128 Academia Road Section 2, Nan-Kang, Taipei 11529, Taiwan.,Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan.,Graduate Institute of Biotechnology and Biotechnology Center, National Chung-Hsing University, Taichung 40227, Taiwan
| | - Sheng-Cih Huang
- Applied Chemistry Department, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu City 300093Taiwan, R.O.C
| | - Chun-Hung Lin
- Institute of Biological Chemistry, Academia Sinica, No.128 Academia Road Section 2, Nan-Kang, Taipei 11529, Taiwan.,Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan.,Graduate Institute of Biotechnology and Biotechnology Center, National Chung-Hsing University, Taichung 40227, Taiwan.,Department of Chemistry and Institute of Biochemical Sciences, National Taiwan University, Taipei 10617, Taiwan
| | - Kwok-Kong Tony Mong
- Applied Chemistry Department, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu City 300093Taiwan, R.O.C
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2
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Guo T, Zhou D, Yang Y, Zhang X, Chen G, Lin B, Sun Y, Ni H, Liu J, Hou Y, Li N. Bioactive sesquiterpene coumarins from the resin of Ferula sinkiangensis targeted on over-activation of microglia. Bioorg Chem 2020; 104:104338. [PMID: 33142410 DOI: 10.1016/j.bioorg.2020.104338] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 09/18/2020] [Accepted: 09/30/2020] [Indexed: 12/21/2022]
Abstract
Nine undescribed (1-4, 6-10) sesquiterpene coumarins, together with a new natural one (5) and ten known ones (11-20), were isolated from the low polarity fraction of the 95% ethanol extract of the resin of Ferula sinkiangensis. Their structures were elucidated based on the comprehensive analysis of HRESIMS, 1D and 2D NMR data. The absolute configurations were determined by comparison of experimental and calculated ECD spectra. All the identified SCs were evaluated for their anti-neuroinflammatory activities in LPS-induced BV-2 cells. Ferusingensine G (8) displayed a significant inhibitory effect on nitric oxide (NO) production with an IC50 value of 1.2 μM. The results suggested that natural SCs might be served as potential neuroinflammatory inhibitors.
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Affiliation(s)
- Tingting Guo
- School of Traditional Chinese Materia Medica, Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research & Development, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning Province, China
| | - Di Zhou
- School of Traditional Chinese Materia Medica, Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research & Development, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning Province, China
| | - Yanqiu Yang
- College of Life and Health Sciences, Northeastern University, Shenyang 110004, China; State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Guangxi Normal University, Guilin, China
| | - Xueni Zhang
- School of Traditional Chinese Materia Medica, Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research & Development, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning Province, China
| | - Gang Chen
- School of Traditional Chinese Materia Medica, Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research & Development, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning Province, China
| | - Bin Lin
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Yu Sun
- XinJiang Institute of Chinese Materia Medica and Ethnodrug, Urumqi 830002, China
| | - Hui Ni
- XinJiang Institute of Chinese Materia Medica and Ethnodrug, Urumqi 830002, China
| | - Jingyu Liu
- College of Life and Health Sciences, Northeastern University, Shenyang 110004, China; State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Guangxi Normal University, Guilin, China
| | - Yue Hou
- College of Life and Health Sciences, Northeastern University, Shenyang 110004, China; State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Guangxi Normal University, Guilin, China.
| | - Ning Li
- School of Traditional Chinese Materia Medica, Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research & Development, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning Province, China.
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3
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Inuki S, Fujimoto Y. Total synthesis of naturally occurring chiral cyclopropane fatty acids and related compounds. Tetrahedron Lett 2019. [DOI: 10.1016/j.tetlet.2019.03.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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4
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Mato M, García‐Morales C, Echavarren AM. Generation of Gold(I) Carbenes by Retro‐Buchner Reaction: From Cyclopropanes to Natural Products Synthesis. ChemCatChem 2018. [DOI: 10.1002/cctc.201801201] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Mauro Mato
- Institute of Chemical Research of Catalonia (ICIQ)Barcelona Institute of Science and Technology (BIST) Av. Països Catalans 16 43007 Tarragona Spain
- Departament de Química Analítica i Química OrgànicaUniversitat Rovira i Virgili C/Marcel⋅li Domingo s/n 43007 Tarragona Spain
| | - Cristina García‐Morales
- Institute of Chemical Research of Catalonia (ICIQ)Barcelona Institute of Science and Technology (BIST) Av. Països Catalans 16 43007 Tarragona Spain
- Departament de Química Analítica i Química OrgànicaUniversitat Rovira i Virgili C/Marcel⋅li Domingo s/n 43007 Tarragona Spain
| | - Antonio M. Echavarren
- Institute of Chemical Research of Catalonia (ICIQ)Barcelona Institute of Science and Technology (BIST) Av. Països Catalans 16 43007 Tarragona Spain
- Departament de Química Analítica i Química OrgànicaUniversitat Rovira i Virgili C/Marcel⋅li Domingo s/n 43007 Tarragona Spain
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5
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Iwasaki T, Terahigashi S, Wang Y, Tanaka A, Zhao H, Fujimoto Y, Fukase K, Kambe N. Synthesis of Cyclopropane Fatty Acids by C( sp3)−C( sp3) Cross-Coupling Reaction and Formal Synthesis of α-Mycolic Acid. Adv Synth Catal 2018. [DOI: 10.1002/adsc.201800901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Takanori Iwasaki
- Department of Applied Chemistry, Graduate School of Engineering; Osaka University, Suita; Osaka 565-0871 Japan
- Department of Chemistry and Biotechnology, Graduate School of Engineering; The University of Tokyo; 7-3-1 Hongo, Bunkyo-ku Tokyo 113-8656 Japan
| | - Shohei Terahigashi
- Department of Applied Chemistry, Graduate School of Engineering; Osaka University, Suita; Osaka 565-0871 Japan
| | - Yufei Wang
- Department of Applied Chemistry, Graduate School of Engineering; Osaka University, Suita; Osaka 565-0871 Japan
| | - Arisa Tanaka
- Department of Applied Chemistry, Graduate School of Engineering; Osaka University, Suita; Osaka 565-0871 Japan
| | - Hanqing Zhao
- Department of Applied Chemistry, Graduate School of Engineering; Osaka University, Suita; Osaka 565-0871 Japan
| | - Yukari Fujimoto
- Department of Chemistry, Faculty of Science and Technology; Keio University; 3-14-1 Hiyoshi, Kohoku-ku, Yokohama Kanagawa 223-8522 Japan
| | - Koichi Fukase
- Department of Chemistry, Graduate School of Science; Osaka University, Toyonaka; Osaka 560-0043 Japan
| | - Nobuaki Kambe
- Department of Applied Chemistry, Graduate School of Engineering; Osaka University, Suita; Osaka 565-0871 Japan
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6
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Mato M, Herlé B, Echavarren AM. Cyclopropanation by Gold- or Zinc-Catalyzed Retro-Buchner Reaction at Room Temperature. Org Lett 2018; 20:4341-4345. [PMID: 29975067 DOI: 10.1021/acs.orglett.8b01791] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Through the design of a second generation of more reactive 7-substituted 1,3,5-cycloheptatrienes, a room-temperature gold(I)-catalyzed retro-Buchner-cyclopropanation sequence and the first zinc(II)-catalyzed version of this process, which uses inexpensive ZnBr2 as catalyst, have been developed. This led to a broad-scope cyclopropanation of both activated and unactivated alkenes, including late-stage derivatization of biologically relevant compounds, and to the total synthesis of (±)-lactobacillic acid.
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Affiliation(s)
- Mauro Mato
- Institute of Chemical Research of Catalonia (ICIQ) , Barcelona Institute of Science and Technology , Av. Països Catalans 16 , 43007 Tarragona , Spain.,Departament de Química Analítica i Química Orgànica , Universitat Rovira i Virgili , C/Marcel·li Domingo s/n , 43007 Tarragona , Spain
| | - Bart Herlé
- Institute of Chemical Research of Catalonia (ICIQ) , Barcelona Institute of Science and Technology , Av. Països Catalans 16 , 43007 Tarragona , Spain
| | - Antonio M Echavarren
- Institute of Chemical Research of Catalonia (ICIQ) , Barcelona Institute of Science and Technology , Av. Països Catalans 16 , 43007 Tarragona , Spain.,Departament de Química Analítica i Química Orgànica , Universitat Rovira i Virgili , C/Marcel·li Domingo s/n , 43007 Tarragona , Spain
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7
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Shah S, White JM, Williams SJ. Total syntheses of cis-cyclopropane fatty acids: dihydromalvalic acid, dihydrosterculic acid, lactobacillic acid, and 9,10-methylenehexadecanoic acid. Org Biomol Chem 2014; 12:9427-38. [DOI: 10.1039/c4ob01863j] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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9
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Palko JW, Buist PH, Manthorpe JM. A flexible and modular stereoselective synthesis of (9R,10S)-dihydrosterculic acid. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.tetasy.2013.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Zhang Z, Zong C, Song G, Lv G, Chun Y, Wang P, Ding N, Li Y. Total synthesis of caminoside B, a novel antimicrobial glycolipid isolated from the marine sponge Caminus sphaeroconia. Carbohydr Res 2010; 345:750-60. [DOI: 10.1016/j.carres.2010.01.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2009] [Revised: 01/21/2010] [Accepted: 01/25/2010] [Indexed: 10/19/2022]
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11
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Cheeseman M, Davies IR, Axe P, Johnson AL, Bull SD. A temporary stereocentre approach for the asymmetric synthesis of chiral cyclopropane-carboxaldehydes. Org Biomol Chem 2009; 7:3537-48. [PMID: 19675911 DOI: 10.1039/b908600e] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Matt Cheeseman
- Department of Chemistry, University of Bath, Bath, UK BA2 7AY
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12
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13
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Baimashev BA, Fedorenko VY, Polozov AM, Shtyrlin YG, Klimovitskii EN. Cyclopropanecarbaldehyde with two protected hydroxymethyl groups. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2007. [DOI: 10.1134/s107042800706019x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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14
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Abstract
Cyclopropane FA occur in nature in the phosphoplipids of bacterial membranes, in oils containing cyclopropene FA, and in Litchi sinensis oil. Dihydrosterculic acid (2-octyl cyclopropaneoctanoic acid) and its methyl ester were selected for 1H and 13C NMR analysis as compounds representative of cyclopropane FA. The 500 MHz 1H NMR spectra acquired with CDCl3 as solvent show two individual peaks at -0.30 and 0.60 ppm for the methylene protons of the cyclopropane ring. Assignments were made with the aid of 2D correlations. In accordance with previous literature, the upfield signal is assigned to the cis proton and the downfield signal to the trans proton. This signal of the trans proton is resolved from the peak of the two methine protons of the cyclopropane ring, which is located at 0.68 ppm. The four protons attached to the two methylene carbons alpha to the cyclopropane ring also show a split signal. Two of these protons, one from each methylene moiety, display a distinct shift at 1.17 ppm, and the signal of the other two protons is observed at 1.40 ppm, within the broad methylene peak. The characteristic peaks in the 13C spectra are also assigned.
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Affiliation(s)
- Gerhard Knothe
- National Center for Agricultural Utilization Research, Agricultural Research Service, US Department of Agriculture, Peoria, IL 61604, USA.
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15
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Al-Dulayymi JR, Baird MS, Mohammed H, Roberts E, Clegg W. The synthesis of one enantiomer of the α-methyl-trans-cyclopropane unit of mycolic acids. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.03.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Roberts IO, Baird MS. A new short synthesis of 10R-tuberculostearic acid and its enantiomer. Chem Phys Lipids 2006; 142:111-7. [PMID: 16690044 DOI: 10.1016/j.chemphyslip.2006.03.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2005] [Revised: 03/11/2006] [Accepted: 03/16/2006] [Indexed: 11/21/2022]
Abstract
Tuberculostearic acid (10R-methyloctadecanoic acid) and its 10S-enantiomer were synthesised by a chiral pool strategy, in four steps from citronellyl bromide.
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Affiliation(s)
- Ieuan O Roberts
- Department of Chemistry, University of Wales, Bangor, Gwynedd, Wales LL57 2UW, UK
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17
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Stuart LJ, Buck JP, Tremblay AE, Buist PH. Configurational analysis of cyclopropyl fatty acids isolated from Escherichia coli. Org Lett 2006; 8:79-81. [PMID: 16381572 DOI: 10.1021/ol052550d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] The absolute configuration of methyl lactobacillate and its 9,10 homologue, both isolated from Escherichia coli B-ATCC 11303, was found to be 11R,12S and 9R,10S, respectively.
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Affiliation(s)
- Laura J Stuart
- Department of Chemistry, Carleton University, Ottawa, Ontario
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18
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Al Dulayymi JR, Baird MS, Roberts E. The synthesis of a single enantiomer of a major α-mycolic acid of M. tuberculosis. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.09.056] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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19
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Cheeseman M, Feuillet FJP, Johnson AL, Bull SD. A novel strategy for the asymmetric synthesis of chiral cyclopropane carboxaldehydes. Chem Commun (Camb) 2005:2372-4. [PMID: 15877132 DOI: 10.1039/b501847a] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new way of combining chiral auxiliaries and substrate-directable reactions for asymmetric synthesis is described that employs a three-step sequence of aldol-cyclopropanation-retro-aldol reactions for the stereoselective synthesis of enantiopure cyclopropane carboxaldehydes.
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21
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Coxon GD, Al Dulayymi JR, Morehouse C, Brennan PJ, Besra GS, Baird MS, Minnikin DE. Synthesis and properties of methyl 5-(1'R,2'S)-(2-octadecylcycloprop-1-yl)pentanoate and other omega-19 chiral cyclopropane fatty acids and esters related to mycobacterial mycolic acids. Chem Phys Lipids 2004; 127:35-46. [PMID: 14706739 DOI: 10.1016/j.chemphyslip.2003.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A 23-26-carbon chain length range of omega-19 (1'R,2'S) cyclopropane fatty acids, related to mycobacterial mycolic acids, has been prepared. The key cyclopropyl intermediate, (1'R,2'S)-(Z)-1-formyl-2-octadecylcyclopropane, underwent Wittig chemistry with various reagents to provide vinylic precursors, which were selectively reduced to the corresponding saturated omega-19 cyclopropane fatty acids or esters. The 24-carbon omega-19 cyclopropane ester was made by chain elongation of the 23-carbon ester. Saturated and unsaturated chiral cyclopropane acids and esters were assayed, using wall extracts of Mycobacterium smegmatis; the incorporation of 14C-acetate was used to measure inhibition or stimulation of mycolic acid synthesis. Minor inhibition (2-3%) was shown by the 23- and 24-carbon saturated esters; all the other compounds were stimulants. The most effective (38-55%) stimulators of mycolate synthesis were the unsaturated esters with 23- and 26-carbons and the saturated and unsaturated 25-carbon acids.
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Affiliation(s)
- Geoffrey D Coxon
- Department of Chemistry, University of Newcastle, Newcastle upon Tyne NE1 7RU, UK
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Lou Y, Horikawa M, Kloster RA, Hawryluk NA, Corey EJ. A New Chiral Rh(II) Catalyst for Enantioselective [2 + 1]-Cycloaddition. Mechanistic Implications and Applications. J Am Chem Soc 2004; 126:8916-8. [PMID: 15264821 DOI: 10.1021/ja047064k] [Citation(s) in RCA: 175] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel chiral Rh(II) catalyst (1) is introduced for the [2 + 1]-cycloaddition of ethyl diazoacetate to terminal acetylenes and olefins with high enantioselectivity. The catalyst 1 consists of one acetate bridging group and three mono-N-triflyldiphenylimidazoline-2-one bidentate ligands (DPTI) spanning the Rh(II)-Rh(II) metallic center in a structure that was determined by single-crystal X-ray diffraction analysis. A rational mechanism is advanced that provides a straightforward explanation for the enantioselectivity and absolute stereochemical course of the [2 + 1]-cycloaddition reactions. A key element in this explanation is the cleavage of one of the Rh-O bonds of the bridging acetate group in the intermediate Rh-carbene complex to form a new pentacoordinate Rh carbene complex (formally 1.5 valent Rh) that can undergo [2 + 2]-cycloaddition with the C-C pi-bond of the acetylenic or olefinic substrate. Reductive elimination of the resulting adduct affords the cyclopropene or cyclopropane product. The C2-symmetry of the two DPTI ligands orthogonal to the bridging acetate also contributes to the high observed enantioselectivity and mechanistic clarity. The catalyst 1, which functions effectively at 0.5 mol %, can be recovered efficiently for reuse. Its ready availability, robustness, and effectiveness suggest it as a useful addition to the list of practical chiral Rh(II) catalysts for synthesis.
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Affiliation(s)
- Yan Lou
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, 02138, USA
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23
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The absolute configuration of methyl dihydrosterculate: an unusual phytofatty acid isolated from the seed oil of Litchi chinensis. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2003.12.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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