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Total synthesis of (+/-)-calcaridine A and (+/-)-epi-calcaridine A.

ABSTRACT: The first total synthesis of the Leucetta alkaloid calcaridine A is described based on a biosynthetic postulate. Application of an oxidative rearrangement of a 4,5-disubstituted imidazole leads to the formation of both calcaridine A and epi-calcaridine A. An X-ray crystal structure determination on the latter has allowed the assignment of the relative configuration of the epimeric natural product and calcaridine A by extrapolation.

SUBMITTER: Koswatta PB

PROVIDER: S-EPMC2650485 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Total synthesis of (+/-)-calcaridine A and (+/-)-epi-calcaridine A.

Koswatta Panduka B PB Sivappa Rasapalli R Dias H V Rasika HV Lovely Carl J CJ

Organic letters 20080925 21

The first total synthesis of the Leucetta alkaloid calcaridine A is described based on a biosynthetic postulate. Application of an oxidative rearrangement of a 4,5-disubstituted imidazole leads to the formation of both calcaridine A and epi-calcaridine A. An X-ray crystal structure determination on the latter has allowed the assignment of the relative configuration of the epimeric natural product and calcaridine A by extrapolation. ...[more]

PMID: 18816134

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