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Total synthesis of the reported structure of 13a-hydroxytylophorine.

ABSTRACT: The first total synthesis of the reported structure of 13a-hydroxytylophorine was accomplished. The key step was an unprecedented NaBH4-promoted one-pot reductive cyclization cascade that efficiently yielded a hydroxyl azonane intermediate. The indolizidine framework was obtained by means of oxidation and a subsequent unexpected protecting-group migration. This total synthesis revealed that the reported structure of the naturally isolated compound is incorrect.

SUBMITTER: Zhang H

PROVIDER: S-EPMC5716997 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Total synthesis of the reported structure of 13a-hydroxytylophorine.

Zhang Hui H Li Gang G Su Bo B Deng Meng M Liu Yu-Xiu YX Gu Yu-Cheng YC Wang Qing-Min QM

Scientific reports 20171205 1

The first total synthesis of the reported structure of 13a-hydroxytylophorine was accomplished. The key step was an unprecedented NaBH<sub>4</sub>-promoted one-pot reductive cyclization cascade that efficiently yielded a hydroxyl azonane intermediate. The indolizidine framework was obtained by means of oxidation and a subsequent unexpected protecting-group migration. This total synthesis revealed that the reported structure of the naturally isolated compound is incorrect. ...[more]

PMID: 29208905

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