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Biomimetic Total Syntheses of (-)-Leucoridines?A and C through the Dimerization of (-)-Dihydrovalparicine.

ABSTRACT: Concise biomimetic syntheses of the Strychnos-Strychnos-type bis-indole alkaloids (-)-leucoridine?A (1) and C (2) were accomplished through the biomimetic dimerization of (-)-dihydrovalparicine (3). En?route to 3, the known alkaloids (+)-geissoschizoline (8) and (-)-dehydrogeissoschizoline (10) were also prepared. DFT calculations were employed to elucidate the mechanism, which favors a stepwise aza-Michael/spirocyclization sequence over the alternate hetero-Diels-Alder cycloaddition reaction.

SUBMITTER: Kokkonda P

PROVIDER: S-EPMC5012216 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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