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Regiospecific, enantiospecific total synthesis of C-19 methyl substituted sarpagine alkaloids dihydroperaksine-17-al and dihydroperaksine.

ABSTRACT: The optically active tetracyclic ketone 8 was converted into the pentacylic core 14 of the C-19 methyl substituted N(a)-H sarpagine and ajmaline alkaloids via a critical haloboration reaction. The ketone 14 was then employed in the total synthesis of 19(S),20(R)-dihydroperaksine-17-al (1) and 19(S),20(R)-dihydroperaksine (2). The key regioselective hydroboration and controlled oxidation-epimerization sequence developed in this approach should provide a general method to functionalize the C(20)-C(21) double bond in the ajmaline-related indole alkaloids.

SUBMITTER: Edwankar RV

PROVIDER: S-EPMC3184356 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Regiospecific, enantiospecific total synthesis of C-19 methyl substituted sarpagine alkaloids dihydroperaksine-17-al and dihydroperaksine.

Edwankar Rahul V RV Edwankar Chitra R CR Deschamps Jeffrey J Cook James M JM

Organic letters 20110830 19

The optically active tetracyclic ketone 8 was converted into the pentacylic core 14 of the C-19 methyl substituted N(a)-H sarpagine and ajmaline alkaloids via a critical haloboration reaction. The ketone 14 was then employed in the total synthesis of 19(S),20(R)-dihydroperaksine-17-al (1) and 19(S),20(R)-dihydroperaksine (2). The key regioselective hydroboration and controlled oxidation-epimerization sequence developed in this approach should provide a general method to functionalize the C(20)-C ...[more]

PMID: 21877687

Similar Datasets

General strategy for synthesis of C-19 methyl-substituted sarpagine/macroline/ajmaline indole alkaloids including total synthesis of 19(S),20(R)-dihydroperaksine, 19(S),20(R)-dihydroperaksine-17-al, and peraksine.

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