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Enantioselective synthesis of Iboga alkaloids and vinblastine via rearrangements of quaternary ammoniums.

ABSTRACT: An efficient and novel strategy for the enantioselective syntheses of various iboga alkaloids has been developed. The salient features include a gold-catalyzed oxidation of a terminal alkyne followed by cyclization, a Stevens rearrangement and a tandem sequence that combines the gold-catalyzed oxidation, cyclization and [1,2]-shift. The catharanthine analogs provided by our approach were further converted to the vinca alkaloid vinblastine and its analogs, which confirmed the remarkable sensitivity of the cytotoxicity to the C20' substituent of vinblastine.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC6021789 | biostudies-other | 2016 Aug

REPOSITORIES: biostudies-other

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Enantioselective synthesis of Iboga alkaloids and vinblastine via rearrangements of quaternary ammoniums.

Zhang Yun Y Xue Yibin Y Li Gang G Yuan Haosen H Luo Tuoping T

Chemical science 20160516 8

An efficient and novel strategy for the enantioselective syntheses of various iboga alkaloids has been developed. The salient features include a gold-catalyzed oxidation of a terminal alkyne followed by cyclization, a Stevens rearrangement and a tandem sequence that combines the gold-catalyzed oxidation, cyclization and [1,2]-shift. The catharanthine analogs provided by our approach were further converted to the vinca alkaloid vinblastine and its analogs, which confirmed the remark ...[more]

PMID: 30034694

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