1
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Farrar EHE, Grayson MN. Noncovalent Interactions in the Oxazaborolidine-Catalyzed Enantioselective Mukaiyama Aldol. J Org Chem 2022; 87:10054-10061. [PMID: 35849546 PMCID: PMC9361351 DOI: 10.1021/acs.joc.2c01039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
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Current models for oxazaborolidine-catalyzed transition-state
structures
are determined by C–H···O–B and C–H···O=S
formyl hydrogen bonding between the electrophile and catalyst. However,
selectivity in the oxazaborolidine-catalyzed Mukaiyama aldol cannot
be fully rationalized using these models. Combined density functional
theory and noncovalent interaction analyses reveal a new reaction
model relying on C–H···O, C–H···π,
and π–π interactions between the nucleophile, electrophile,
and catalyst to induce selectivity.
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Affiliation(s)
- Elliot H E Farrar
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Matthew N Grayson
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
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2
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Nakazato K, Oda M, Fuwa H. Total Synthesis of (+)-Neopeltolide by the Macrocyclization/Transannular Pyran Cyclization Strategy. Org Lett 2022; 24:4003-4008. [PMID: 35649194 DOI: 10.1021/acs.orglett.2c01429] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An 11-step synthesis of (+)-neopeltolide was developed. The C1-C7 carboxylic acid and the C8-C16 alcohol were prepared, each in six steps, from (R)- and (S)-epichlorohydrin, respectively. After esterification, our tandem macrocyclization/transannular pyran cyclization strategy was applied to a stereocontrolled construction of the neopeltolide macrolactone. The side chain was synthesized in six steps from ethyl 4-oxazolecarboxylate through palladium-catalyzed cross-couplings. A Mitsunobu reaction of the neopeltolide macrolactone and the side chain completed the synthesis.
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Affiliation(s)
- Kazuki Nakazato
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Mami Oda
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Haruhiko Fuwa
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
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3
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Fariña-Ramos M, García C, Martín VS, Álvarez-Méndez SJ. Synthetic efforts on the road to marine natural products bearing 4- O-2,3,4,6-tetrasubstituted THPs: an update. RSC Adv 2021; 11:5832-5858. [PMID: 35423108 PMCID: PMC8694735 DOI: 10.1039/d0ra10755g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 01/26/2021] [Indexed: 11/21/2022] Open
Abstract
Scientific literature is inundated with secondary metabolites from marine sources. In this ocean of natural products, the presence of recurring patterns has traditionally led scientists to unravel the biosynthetic mechanisms that naturally yield these products, as well as to imitate Nature to prepare them in the laboratory, especially when promising bioactivities and stimulating molecular architectures are involucrate. For instance, natural products containing multisubstituted oxygenated rings and macrocyclic lactones are recurrently selected as targets for developing total syntheses. Thus, in the last decades a noteworthy number of synthetic works regarding miyakolide, madeirolide A and representative compounds of polycavernosides, lasonolides and clavosolides have come to fruition. Up to now, these families of macrolides are the only marine natural products bearing a tetrasubstituted tetrahydropyran ring with carbon substituents at positions 2, 3 and 6, as well as an oxygen at position 4. Their splendid structures have received the attention of the synthetic community, up to the point of starring in dozens of articles, and even some reviews. This work covers all the synthetic studies towards miyakolide and madeirolide A, as well as the synthetic efforts performed after the previous specialised reviews about lasonolide A, polycavernoside A and clavosolides, published in 2006, 2007 and 2016, respectively. In total, this review summarises 22 articles in which these marine natural products with 4-O-2,3,4,6-tetrasubstituted tetrahydropyrans have the leading role.
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Affiliation(s)
- Marta Fariña-Ramos
- Departamento de Química Orgánica, Universidad de La Laguna Avda Astrofísico Francisco Sánchez 38206 La Laguna Tenerife Spain
- Instituto Universitario de Bio-Orgánica Antonio González, Síntesis Orgánica Sostenible, Unidad Asociada al CSIC, Universidad de La Laguna Avda Astrofísico Francisco Sánchez 38206 La Laguna Tenerife Spain
| | - Celina García
- Departamento de Química Orgánica, Universidad de La Laguna Avda Astrofísico Francisco Sánchez 38206 La Laguna Tenerife Spain
- Instituto Universitario de Bio-Orgánica Antonio González, Síntesis Orgánica Sostenible, Unidad Asociada al CSIC, Universidad de La Laguna Avda Astrofísico Francisco Sánchez 38206 La Laguna Tenerife Spain
| | - Víctor S Martín
- Departamento de Química Orgánica, Universidad de La Laguna Avda Astrofísico Francisco Sánchez 38206 La Laguna Tenerife Spain
- Instituto Universitario de Bio-Orgánica Antonio González, Síntesis Orgánica Sostenible, Unidad Asociada al CSIC, Universidad de La Laguna Avda Astrofísico Francisco Sánchez 38206 La Laguna Tenerife Spain
| | - Sergio J Álvarez-Méndez
- Departamento de Química Orgánica, Universidad de La Laguna Avda Astrofísico Francisco Sánchez 38206 La Laguna Tenerife Spain
- Instituto Universitario de Bio-Orgánica Antonio González, Síntesis Orgánica Sostenible, Unidad Asociada al CSIC, Universidad de La Laguna Avda Astrofísico Francisco Sánchez 38206 La Laguna Tenerife Spain
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4
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Takemoto Y, Tokuhiro Y, Hayama N, Kobayashi Y. Bifunctional-Benzothiadiazine-Catalyzed Regio- and Stereoselective Aldol Reactions Using A 1,3-Acetonedicarboxylic Acid Monoester. HETEROCYCLES 2021. [DOI: 10.3987/com-20-s(k)12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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5
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Fuwa H. Structure determination, correction, and disproof of marine macrolide natural products by chemical synthesis. Org Chem Front 2021. [DOI: 10.1039/d1qo00481f] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Integration of chemical synthesis, NMR spectroscopy, and various analytical means is key to success in the structure elucidation of stereochemically complex marine macrolide natural products.
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Affiliation(s)
- Haruhiko Fuwa
- Department of Applied Chemistry
- Faculty of Science and Engineering
- Chuo University
- Tokyo 112-8551
- Japan
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6
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Lam NYS, Paterson I. Stereocontrolled Synthesis as an Enabling Tool for the Configurational Assignment of Marine Polyketide Natural Products. European J Org Chem 2019. [DOI: 10.1002/ejoc.201901243] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Nelson Y. S. Lam
- University Chemical Laboratory; Lensfield Road CB2 1EW Cambridge United Kingdom
| | - Ian Paterson
- University Chemical Laboratory; Lensfield Road CB2 1EW Cambridge United Kingdom
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7
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Lam NYS, Muir G, Challa VR, Britton R, Paterson I. A counterintuitive stereochemical outcome from a chelation-controlled vinylmetal aldehyde addition leads to the configurational reassignment of phormidolide A. Chem Commun (Camb) 2019; 55:9717-9720. [DOI: 10.1039/c9cc05067a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Detailed NMR spectroscopic comparisons of a series of synthetic C10–C23 fragments with a known derivative of phormidolide A resulted in the configurational reassignment of seven of its 11 stereocentres.
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Affiliation(s)
| | - Garrett Muir
- Department of Chemistry
- Simon Fraser University
- Burnaby
- Canada
| | | | - Robert Britton
- Department of Chemistry
- Simon Fraser University
- Burnaby
- Canada
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8
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Hale KJ, Manaviazar S, Watson HA. The O‐Directed Free Radical Hydrostannation of Propargyloxy Dialkyl Acetylenes with Ph3SnH/cat. Et3B. A Refutal of the Stannylvinyl Cation Mechanism. CHEM REC 2018; 19:238-319. [DOI: 10.1002/tcr.201700104] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 09/04/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Karl J. Hale
- School of Chemistry and Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB)Queen's University Belfast Stranmillis Road Belfast BT9 5AG, Northern Ireland United Kingdom
| | - Soraya Manaviazar
- School of Chemistry and Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB)Queen's University Belfast Stranmillis Road Belfast BT9 5AG, Northern Ireland United Kingdom
| | - Hamish A. Watson
- School of Chemistry and Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB)Queen's University Belfast Stranmillis Road Belfast BT9 5AG, Northern Ireland United Kingdom
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9
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Iwasaki K, Sasaki S, Kasai Y, Kawashima Y, Sasaki S, Ito T, Yotsu-Yamashita M, Sasaki M. Total Synthesis of Polycavernosides A and B, Two Lethal Toxins from Red Alga. J Org Chem 2017; 82:13204-13219. [PMID: 29124933 DOI: 10.1021/acs.joc.7b02293] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Polycavernosides A and B are glycosidic macrolide natural products isolated as the toxins causing fatal human poisoning by the edible red alga Gracilaria edulis (Polycavernosa tsudai). Total synthesis of polycavernosides A and B has been achieved via a convergent approach. The synthesis of the macrolactone core structure is highlighted by the catalytic asymmetric syntheses of the two key fragments using hetero-Diels-Alder reaction and Kiyooka aldol reaction as the key steps, their union through Suzuki-Miyaura coupling, and Keck macrolactonization. Finally, glycosylation with the l-fucosyl-d-xylose unit and construction of the polyene side chain through Stille coupling completed the total synthesis of polycavernosides A and B.
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Affiliation(s)
- Kotaro Iwasaki
- Graduate School of Life Sciences, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Satori Sasaki
- Graduate School of Life Sciences, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Yusuke Kasai
- Graduate School of Life Sciences, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Yuki Kawashima
- Graduate School of Life Sciences, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Shohei Sasaki
- Graduate School of Life Sciences, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Takanori Ito
- Graduate School of Life Sciences, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Mari Yotsu-Yamashita
- Graduate School of Agricultural Science, Tohoku University , 468-1 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Makoto Sasaki
- Graduate School of Life Sciences, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
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10
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The value of 2 J P–CO as a diagnostic parameter for the structure and thermal reactivity of carbonyl-stabilised phosphonium ylides. Tetrahedron 2017. [DOI: 10.1016/j.tet.2017.09.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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11
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Busch T, Dräger G, Kunst E, Benson H, Sasse F, Siems K, Kirschning A. Synthesis and antiproliferative activity of new tonantzitlolone-derived diterpene derivatives. Org Biomol Chem 2016; 14:9040-5. [PMID: 27604289 DOI: 10.1039/c6ob01697a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The synthesis of the diterpene (+)-tonantzitlolone A and a series of derivatives is reported. The study includes the determination of their antiproliferative activities against selected cancer cell lines.
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Affiliation(s)
- Torsten Busch
- Institut für Organische Chemie and Biomolekulares Wirkstoffzentrum (BMWZ), Leibniz Universität Hannover, Schneiderberg 1b, 30167 Hannover, Germany.
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12
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Hale KJ, Maczka M, Kaur A, Manaviazar S, Ostovar M, Grabski M. Synthesis of the C(7)–C(22) Sector of (+)-Acutiphycin via O-Directed Double Free Radical Alkyne Hydrostannation with Ph3SnH/Et3B, Double I–Sn Exchange, and Double Stille Coupling. Org Lett 2014; 16:1168-71. [DOI: 10.1021/ol500050p] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Karl J. Hale
- The School of Chemistry & Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB), the Queen’s University Belfast, Stranmillis Road, Belfast BT9 5AG, Northern Ireland, United Kingdom
| | - Maciej Maczka
- The School of Chemistry & Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB), the Queen’s University Belfast, Stranmillis Road, Belfast BT9 5AG, Northern Ireland, United Kingdom
| | - Amarjit Kaur
- The School of Chemistry & Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB), the Queen’s University Belfast, Stranmillis Road, Belfast BT9 5AG, Northern Ireland, United Kingdom
| | - Soraya Manaviazar
- The School of Chemistry & Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB), the Queen’s University Belfast, Stranmillis Road, Belfast BT9 5AG, Northern Ireland, United Kingdom
| | - Mehrnoosh Ostovar
- The
Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - Milosz Grabski
- The School of Chemistry & Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB), the Queen’s University Belfast, Stranmillis Road, Belfast BT9 5AG, Northern Ireland, United Kingdom
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13
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Bariotaki A, Kalaitzakis D, Smonou I. Enzymatic reductions for the regio- and stereoselective synthesis of hydroxy-keto esters and dihydroxy esters. Org Lett 2012; 14:1792-5. [PMID: 22409731 DOI: 10.1021/ol3003833] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ketoreductases were utilized for the stereoselective synthesis of δ-hydroxy-β-keto esters, β-hydroxy-δ-keto esters, and β,δ-dihydroxy esters. Seven out of eight possible stereoisomers were obtained from the enzymatic reduction of the corresponding β,δ-diketo ester in high enantio- and diastereomeric excess.
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Affiliation(s)
- Anna Bariotaki
- Department of Chemistry, University of Crete, Heraklion 71003, Crete, Greece
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14
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Hurski AL, Kulinkovich OG. Synthesis of epothilone D with the forced application of oxycyclopropane intermediates. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2011. [DOI: 10.1134/s1070428011110029] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Okamoto M, Irii H, Tahara Y, Ishii H, Hirao A, Udagawa H, Hiramoto M, Yasuda K, Takanishi A, Shibata S, Shimizu I. Synthesis of a new [6]-gingerol analogue and its protective effect with respect to the development of metabolic syndrome in mice fed a high-fat diet. J Med Chem 2011; 54:6295-304. [PMID: 21851089 DOI: 10.1021/jm200662c] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
To determine the effects of a [6]-gingerol analogue (6G), a major chemical component of the ginger rhizome, and its stable analogue after digestion in simulated gastric fluid, aza-[6]-gingerol (A6G), on diet-induced body fat accumulation, we synthesized 6G and A6G. Mice were fed either a control regular rodent chow, a high-fat diet (HFD), or a HFD supplemented with 6G and A6G. Magnetic resonance imaging adiposity parameters of the 6G- and A6G-treated mice were compared with those of control mice. Supplementation with 6G and A6G significantly reduced body weight gain, fat accumulation, and circulating levels of insulin and leptin. The mRNA levels of sterol regulatory element-binding protein 1c (SREBP-1c) and acetyl-CoA carboxylase 1 in the liver were significantly lower in mice fed A6G than in HFD control mice. Our findings indicate that A6G, rather than 6G, enhances energy metabolism and reduces the extent of lipogenesis by downregulating SREBP-1c and its related molecules, which leads to the suppression of body fat accumulation.
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Affiliation(s)
- Mayumi Okamoto
- Department of Applied Chemistry, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo, Japan.
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16
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Hodgson DM, Man S. Synthesis of the Anti-HIV Agent (−)-Hyperolactone C by Using Oxonium Ylide Formation-Rearrangement. Chemistry 2011; 17:9731-7. [DOI: 10.1002/chem.201101082] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Indexed: 11/05/2022]
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17
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Larghi EL, Kaufman TS. Synthesis of Oxacycles Employing the Oxa‐Pictet–Spengler Reaction: Recent Developments and New Prospects. European J Org Chem 2011. [DOI: 10.1002/ejoc.201100271] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Enrique L. Larghi
- Institute of Chemistry of Rosario (IQUIR, CONICET‐UNR)and Department of Organic Chemistry, School of Pharmaceuticaland Biochemical Sciences, National University of Rosario, Suipacha 531 (S2002LRK) Rosario, Argentina, Fax: +54‐341‐4370477, ext. 35
| | - Teodoro S. Kaufman
- Institute of Chemistry of Rosario (IQUIR, CONICET‐UNR)and Department of Organic Chemistry, School of Pharmaceuticaland Biochemical Sciences, National University of Rosario, Suipacha 531 (S2002LRK) Rosario, Argentina, Fax: +54‐341‐4370477, ext. 35
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18
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Villano R, Acocella MR, Scettri A. Synthesis of multifunctionalized building blocks via vinylogous addition of Chan’s diene to carbonyl and carbonyl-related electrophiles, mediated by molecular iodine. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.02.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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19
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Casiraghi G, Battistini L, Curti C, Rassu G, Zanardi F. The Vinylogous Aldol and Related Addition Reactions: Ten Years of Progress. Chem Rev 2011; 111:3076-154. [DOI: 10.1021/cr100304n] [Citation(s) in RCA: 454] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Giovanni Casiraghi
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, I-43124 Parma, Italy
| | - Lucia Battistini
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, I-43124 Parma, Italy
| | - Claudio Curti
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, I-43124 Parma, Italy
| | - Gloria Rassu
- Istituto di Chimica Biomolecolare del CNR, Traversa La Crucca 3, I-07100 Li Punti, Sassari, Italy
| | - Franca Zanardi
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, I-43124 Parma, Italy
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20
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Wu X, Zhou J, Snider BB. Introduction of the (-)-berkelic acid side chain and assignment of the C-22 stereochemistry. J Org Chem 2010; 74:6245-52. [PMID: 19630376 DOI: 10.1021/jo901221a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A Kiyooka aldol condensation of an aldehyde with a trimethylsilyl ketene acetal and the oxazaborolidinone prepared from N-Ts-(S)-valine gives two of the four possible aldol adducts, which were oxidized and deprotected to complete the synthesis of (-)-berkelic acid and (-)-22-epi-berkelic acid. This synthesis establishes the absolute stereochemistry and assigns the stereochemistry at C-22. A biosynthetic pathway is proposed that is consistent with the known absolute stereochemistry at the quaternary carbon of spiciferone A, spicifernin, and berkelic acid and provides a simple explanation for the differing stereochemistry at C-18 and C-19 of spicifernin and berkelic acid.
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Affiliation(s)
- Xiaoxing Wu
- Department of Chemistry MS 015, Brandeis University, Waltham, Massachusetts 02454-9110, USA
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21
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Curti C, Ranieri B, Battistini L, Rassu G, Zambrano V, Pelosi G, Casiraghi G, Zanardi F. Catalytic, Asymmetric Vinylogous Mukaiyama Aldol Reactions of Pyrrole‐ and Furan‐Based Dienoxy Silanes: How the Diene Heteroatom Impacts Stereocontrol. Adv Synth Catal 2010. [DOI: 10.1002/adsc.201000189] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Claudio Curti
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, 43124 Parma, Italy, Fax: (+39)‐0521‐90‐5006; phone: (+39)‐0521‐90‐5079 (C.C.), (+39)‐0521‐90‐5080 (G.C.), (+39)‐0521‐90‐5067 (F.Z.)
| | - Beatrice Ranieri
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, 43124 Parma, Italy, Fax: (+39)‐0521‐90‐5006; phone: (+39)‐0521‐90‐5079 (C.C.), (+39)‐0521‐90‐5080 (G.C.), (+39)‐0521‐90‐5067 (F.Z.)
| | - Lucia Battistini
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, 43124 Parma, Italy, Fax: (+39)‐0521‐90‐5006; phone: (+39)‐0521‐90‐5079 (C.C.), (+39)‐0521‐90‐5080 (G.C.), (+39)‐0521‐90‐5067 (F.Z.)
| | - Gloria Rassu
- Istituto di Chimica Biomolecolare del CNR, Traversa La Crucca 3, 07100 Li Punti, Sassari, Italy
| | - Vincenzo Zambrano
- Istituto di Chimica Biomolecolare del CNR, Traversa La Crucca 3, 07100 Li Punti, Sassari, Italy
| | - Giorgio Pelosi
- Dipartimento di Chimica Generale ed Inorganica, Chimica Analitica, Chimica Fisica, Università degli Studi di Parma, Viale G. P. Usberti 17A, 43124 Parma, Italy
| | - Giovanni Casiraghi
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, 43124 Parma, Italy, Fax: (+39)‐0521‐90‐5006; phone: (+39)‐0521‐90‐5079 (C.C.), (+39)‐0521‐90‐5080 (G.C.), (+39)‐0521‐90‐5067 (F.Z.)
| | - Franca Zanardi
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G. P. Usberti 27A, 43124 Parma, Italy, Fax: (+39)‐0521‐90‐5006; phone: (+39)‐0521‐90‐5079 (C.C.), (+39)‐0521‐90‐5080 (G.C.), (+39)‐0521‐90‐5067 (F.Z.)
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22
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Hurski AL, Kulinkovich OG. Total synthesis of epothilone D by sixfold ring cleavage of cyclopropanol intermediates. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.04.109] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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23
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Kiyooka SI, Matsumoto S, Umezu S, Fujiyama R, Kaneno D. Intramolecular titanium-promoted deoxygenative cyclization to 9-substituted-1,2,3,4-tetrahydrofluorene skeleton. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2009.12.090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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24
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Schäckel R, Hinkelmann B, Sasse F, Kalesse M. The Synthesis of Novel Disorazoles. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.200906450] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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25
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Schäckel R, Hinkelmann B, Sasse F, Kalesse M. The Synthesis of Novel Disorazoles. Angew Chem Int Ed Engl 2010; 49:1619-22. [DOI: 10.1002/anie.200906450] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Yokoyama T, Yokoyama R, Nomura S, Matsumoto S, Fujiyama R, Kiyooka SI. Synthesis of (S)-Ketamine via [1,3]-Chirality Transfer of a Stereocenter Created by Enantioselective Aldol Reaction. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2009. [DOI: 10.1246/bcsj.82.1528] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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27
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Abstract
An extremophilic challenge: Stereospecific condensation of a fully functionalized ketal aldehyde and a 2,6-dihydroxybenzoic acid is the key step in the synthesis of (-)-berkelic acid confirming Fürstner's reassignment of the stereochemistry at C18 and C19, establishing the absolute stereochemistry, and tentatively assigning the stereochemistry at C22.
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Affiliation(s)
- Xiaoxing Wu
- Department of Chemistry, MS 015, Brandeis University, Waltham, MA 02454-9110, USA
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28
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29
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Busch T, Kirschning A. Recent advances in the total synthesis of pharmaceutically relevant diterpenes. Nat Prod Rep 2008; 25:318-41. [DOI: 10.1039/b705652b] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Abstract
Synthetic studies toward the total synthesis of (+)-acutiphycin (1) resulted in the discovery of additive-free, highly regioselective nickel-catalyzed reductive coupling reactions of aldehydes and 1,6-enynes and the construction of an advanced intermediate in studies directed toward the synthesis of 1. Ultimately, although not employing the nickel-catalyzed reaction, a highly convergent total synthesis of (+)-acutiphycin featuring an intermolecular SmI2-mediated Reformatsky coupling reaction and macrolactonization initiated by a retro-ene reaction of an alkoxyalkyne was achieved. The resulting synthesis was 18 steps in the longest linear sequence from either methyl acetoacetate or isobutyraldehyde.
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Affiliation(s)
- Ryan M. Moslin
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139
| | - Timothy F. Jamison
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139
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31
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Batsanov AS, Knowles JP, Lightfoot AP, Maw G, Thirsk CE, Twiddle SJR, Whiting A. A Novel, Efficient, Diastereo- and Enantioselective Mukaiyama Aldol-Based Synthesis of a Vinyl Cyclopentanone Core Derivative of Viridenomycin. Org Lett 2007; 9:5565-8. [DOI: 10.1021/ol7025262] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrei S. Batsanov
- Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, U.K., GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW, U.K., and Pfizer Global Research & Development, Sandwich, Kent CT13 9NJ, U.K
| | - Jonathan P. Knowles
- Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, U.K., GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW, U.K., and Pfizer Global Research & Development, Sandwich, Kent CT13 9NJ, U.K
| | - Andrew P. Lightfoot
- Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, U.K., GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW, U.K., and Pfizer Global Research & Development, Sandwich, Kent CT13 9NJ, U.K
| | - Graham Maw
- Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, U.K., GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW, U.K., and Pfizer Global Research & Development, Sandwich, Kent CT13 9NJ, U.K
| | - Carl E. Thirsk
- Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, U.K., GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW, U.K., and Pfizer Global Research & Development, Sandwich, Kent CT13 9NJ, U.K
| | - Steven J. R. Twiddle
- Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, U.K., GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW, U.K., and Pfizer Global Research & Development, Sandwich, Kent CT13 9NJ, U.K
| | - Andrew Whiting
- Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, U.K., GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW, U.K., and Pfizer Global Research & Development, Sandwich, Kent CT13 9NJ, U.K
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32
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Glushkov VA, Tolstikov AG. Chiral 1,3,2-oxazaborolidines in asymmetric synthesis: recent advances. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc2004v073n06abeh000778] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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33
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Nyavanandi VK, Nadipalli P, Nanduri S, Naidu A, Iqbal J. A cross-metathesis approach for the synthesis of tedanolide and 13-deoxytedanolide: stereoselective synthesis of the C3–C16 segment. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.07.156] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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34
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Sabitha G, Gopal P, Yadav JS. Versatile Approach for the Asymmetric Synthesis of (R)‐ and (S)‐Massoialactones. SYNTHETIC COMMUN 2007. [DOI: 10.1080/00397910701229107] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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35
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Heumann LV, Keck GE. A new construction of 2-alkoxypyrans by an acylation-reductive cyclization sequence. Org Lett 2007; 9:1951-4. [PMID: 17428064 PMCID: PMC2516373 DOI: 10.1021/ol070573h] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new convergent synthetic approach to a pyran motif common to many naturally occurring structures is described. In this approach, two fragments are joined by esterification, and a subsequent intramolecular reductive cyclization affords the 2-hydroxypyran.
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Affiliation(s)
- Lars V Heumann
- Department of Chemistry, University of Utah, Salt Lake City, UT 84112-0850, USA
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36
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Kigoshi H, Hayakawa I. Marine cytotoxic macrolides haterumalides and biselides, and related natural products. CHEM REC 2007; 7:254-64. [PMID: 17663448 DOI: 10.1002/tcr.20119] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Marine animals and plants are rich sources of bioactive natural products. Haterumalides and biselides, isolated from Okinawan marine animals, are 14-membered macrolides with strong cytotoxicity against human cancer cell lines. This review highlights the isolation, structures, bioactivities, and total synthesis of haterumalides, biselides, and related natural products.
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Affiliation(s)
- Hideo Kigoshi
- Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennodai, Tsukuba 305-8571, Japan.
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37
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Gilmour R, Prior TJ, Burton JW, Holmes AB. An organocatalytic approach to the core of eunicellin. Chem Commun (Camb) 2007:3954-6. [PMID: 17896044 DOI: 10.1039/b709322e] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A stereocontrolled synthesis of the core of eunicellin is described featuring a Claisen rearrangement and a diastereoselective organocatalytic Diels-Alder reaction as the key steps.
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Affiliation(s)
- Ryan Gilmour
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UKCB2 1EW
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38
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Abstract
An enantioselective, convergent, total synthesis of (+)-acutiphycin (18 steps, longest linear sequence from commercial materials) features the first application of an alkynyl ether as a macrolactone precursor in total synthesis, as well as the first example of an intermolecular, SmI2-mediated, Reformatsky fragment coupling reaction. The high convergence, efficiency, and modular nature of this synthesis make it amenable to the synthesis of structurally related compounds.
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Affiliation(s)
- Ryan M. Moslin
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139
| | - Timothy F. Jamison
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139
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39
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Backes JR, Koert U. Stereoselective Synthesis of the Monomeric Unit of SCH 351448. European J Org Chem 2006. [DOI: 10.1002/ejoc.200600106] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Jasper C, Wittenberg R, Quitschalle M, Jakupovic J, Kirschning A. Total synthesis and elucidation of the absolute configuration of the diterpene tonantzitlolone. Org Lett 2006; 7:479-82. [PMID: 15673269 DOI: 10.1021/ol047559e] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[structure: see text] The first enantioselective total synthesis of tonantzitlolone, a novel 15-membered macrocyclic diterpene, utilized a Julia olefination, a highly selective, potassium enolate-based anti-Felkin aldol reaction, and an E-selective ring-closing metathesis as key C-C bond-forming steps. The absolute configuration of tonantzitlolone is established.
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Affiliation(s)
- Christian Jasper
- Institut für Organische Chemie der Universität Hannover, Schneiderberg 1B, D-30167 Hannover, Germany
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41
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42
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Crimmins MT, Christie HS, Chaudhary K, Long A. Enantioselective Synthesis of Apoptolidinone: Exploiting the Versatility of Thiazolidinethione Chiral Auxiliaries. J Am Chem Soc 2005; 127:13810-2. [PMID: 16201800 DOI: 10.1021/ja0549289] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An efficient, enantioselective synthesis of apoptolidinone has been completed, demonstrating the versatility of thiazolidinethione auxiliaries. Three propionate aldol additions and two asymmetric glycolate alkylations function to establish 8 of the 12 stereogenic carbon centers. A cross-metathesis reaction is utilized to assemble the C1-C10 trieneoate fragment and the C11-C28 polypropionate region of the molecule.
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Affiliation(s)
- Michael T Crimmins
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
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43
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Wong MW. Roles of C-H...O=S and pi-stacking interactions in the 2-bromoacrolein complex with N-tosyl-(S)-tryptophan-derived oxazaborolidinone catalyst. J Org Chem 2005; 70:5487-93. [PMID: 15989330 DOI: 10.1021/jo050474m] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[structures: see text] Ab initio and density functional calculations were employed to examine the structures and binding energies of various complexes between 2-bromolacrolein and N-tosyl-(S)-tryptophan-derived B-butyl-1,3,2-oxazaborolidin-5-one (NTOB), a catalyst commonly used for Diels-Alder reactions. Our calculations show that the chiral oxazaborolidinone catalyst serves as a tridentate complexation agent via B...O donor-acceptor, C-H...O hydrogen-bonded, and pi-stacking interactions. The most stable complex (1TS) is predicted to have a binding energy of -93 kJ mol(-1) (deltaG(298) = -29 kJ mol(-1)). The formyl C-H...O hydrogen bond and pi-stacking interaction are the key factors governing the relative stabilities of the four acrolein-NTOB complexes examined. The calculated structure and binding properties of 1TS are consistent with the experimental results on the absorption spectrum of the acrolein-NTOB complex and the effects of substituents on the reactivity of Diels-Alder reactions. 1TS differs from Corey's proposed model of transition-state assembly in two aspects: (1) it involves the s-trans-acrolein and (2) it favors a C-H...O interaction via the sulfonyl oxygen (C-H...O=S), rather than the ring oxygen (C-H...O-B). This calculated structure of the acrolein-catalyst complex provides an alternate explanation of the origin of stereoselectivity in the NTOB-catalyzed Diels-Alder reactions.
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Affiliation(s)
- Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543.
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44
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Denmark SE, Heemstra JR, Beutner GL. Katalytische enantioselektive vinyloge Aldolreaktionen. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200462338] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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45
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Denmark SE, Heemstra JR, Beutner GL. Catalytic, Enantioselective, Vinylogous Aldol Reactions. Angew Chem Int Ed Engl 2005; 44:4682-98. [PMID: 15940727 DOI: 10.1002/anie.200462338] [Citation(s) in RCA: 394] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In 1935, R. C. Fuson formulated the principle of vinylogy to explain how the influence of a functional group may be felt at a distant point in the molecule when this position is connected by conjugated double-bond linkages to the group. In polar reactions, this concept allows the extension of the electrophilic or nucleophilic character of a functional group through the pi system of a carbon-carbon double bond. This vinylogous extension has been applied to the aldol reaction by employing "extended" dienol ethers derived from gamma-enolizable alpha,beta-unsaturated carbonyl compounds. Since 1994, several methods for the catalytic, enantioselective, vinylogous aldol reaction have appeared, with which varying degrees of regio- (site), enantio-, and diastereoselectivity can be attained. In this Review, the current scope and limitations of this transformation, as well as its application in natural product synthesis, are discussed.
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Affiliation(s)
- Scott E Denmark
- Roger Adams Laboratory, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA.
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46
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Schopohl MC, Faust A, Mirk D, Fröhlich R, Kataeva O, Waldvogel SR. Synthesis of Rigid Receptors Based on Triphenylene Ketals. European J Org Chem 2005. [DOI: 10.1002/ejoc.200500108] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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47
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Fujiyama R, Goh K, Kiyooka SI. Lewis acid–aldehyde–solvent interactions. A computational approach for determining the critical amount of THF molecules necessary for achieving a high enantioselection in chiral oxazaborolidinone-promoted asymmetric aldol reactions. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2004.12.074] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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48
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Abstract
[reaction: see text] Stille coupling of allylic chloride 26 with vinylstannane 4a afforded 65% of 27 with the requisite skipped diene, vinyl chloride, and allylic oxygen functionality. Yamaguchi macrolactonization of 28 provided 65% of 29, which was elaborated to haterumalide NA methyl ester (32) by a Nozaki-Hiyama-Kishi coupling with 31.
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Affiliation(s)
- Yonghong Gu
- Department of Chemistry, MS 015, Brandeis University, Waltham, Massachusetts 02454-9110, USA
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49
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Villano R, Acocella MR, De Rosa M, Soriente A, Scettri A. Pronounced asymmetric amplification in the aldol condensation of Chan's diene promoted by a Ti(IV)/BINOL complex. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.06.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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50
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