Metal-mediated alkynediol cycloisomerization: first and second generation formal total syntheses of didemniserinolipid B
Title | Metal-mediated alkynediol cycloisomerization: first and second generation formal total syntheses of didemniserinolipid B |
Publication Type | Journal Article |
Year of Publication | 2013 |
Authors | Das, S, Induvadana, B, Ramana, CV |
Journal | Tetrahedron |
Volume | 69 |
Issue | 7 |
Pagination | 1881-1896 |
Date Published | FEB |
ISSN | 0040-4020 |
Keywords | Alkynol-cycloisomerization, Bicyclic ketal, Gold catalysis, Palladium catalysis, Zipper reaction |
Abstract | A formal total synthesis of didemniserinolipid B was developed by employing a regioselective metal-mediated 6-endo-dig alkynol-cycloisomerization reaction. Two routes for the synthesis of key Burke's intermediate have been developed. Our initial approach involved the introduction of a C-17-allcynol followed by Pd-mediated cycloisomerization and then coupling with the serinol unit prior to the introduction of an alpha,beta-unsaturated ester unit through selective oxidation of 1 degrees-OH followed by a two-carbon Wittig homologation. Alternatively, the second generation strategy featuring the serinol coupling with the C-17-alkynol followed by alkyne addition to the epoxide and subsequent Au-mediated cycloisomerization of an acetonide protected alkynediol unit has been executed. This approach has avoided several late stage protection-deprotection events. (C) 2012 Elsevier Ltd. All rights reserved. |
DOI | 10.1016/j.tet.2012.12.045 |
Type of Journal (Indian or Foreign) | Foreign |
Impact Factor (IF) | 2.817 |