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Construction of the Pentacyclic Core and Formal Total Synthesis of (rac)-Renieramycin?T.

ABSTRACT: A formal total synthesis of the antitumor marine natural product (rac)-renieramycin?T, which possesses a characteristic ecteinascidin-type A?ring in the renieramycin-saframycin core skeleton, was elaborated. The key steps in the synthesis of (rac)-renieramycin?T are a modified Pictet-Spengler cyclization of dialkylated oxomalonate derivatives and decarboxylation via a monocarboxylic acid derivative followed by stereocontrolled protonation of the enol intermediate. A key intermediate in our previous synthesis of renieramycin?T was used, and the formal synthesis was accomplished in 21?steps from a known piperazine-2,5-dione derivative.

SUBMITTER: Kimura S

PROVIDER: S-EPMC6173372 | biostudies-other | 2018 Oct

REPOSITORIES: biostudies-other

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Construction of the Pentacyclic Core and Formal Total Synthesis of (rac)-Renieramycin T.

Kimura Shinya S Saito Naoki N

ChemistryOpen 20180807 10

A formal total synthesis of the antitumor marine natural product (rac)-renieramycin T, which possesses a characteristic ecteinascidin-type A ring in the renieramycin-saframycin core skeleton, was elaborated. The key steps in the synthesis of (rac)-renieramycin T are a modified Pictet-Spengler cyclization of dialkylated oxomalonate derivatives and decarboxylation via a monocarboxylic acid derivative followed by stereocontrolled protonation of the enol intermediate. A key intermediat ...[more]

PMID: 30338201

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