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Stereocontrolled Formation of a [4.4]Heterospiro Ring System with Unexpected Inversion of Configuration at the Spirocenter.

ABSTRACT: Stereoselective construction of the 1,3-diazaspiro[4.4]nonane core skeleton of massadine and related dimeric pyrrole-imidazole alkaloids is a synthetic challenge. We describe herein the synthesis of all C13/14 diastereomers of this spiro molecule through controlled oxidation and epimerization of the C13 spirocenter under mild acidic conditions.

SUBMITTER: Ma Z

PROVIDER: S-EPMC5527678 | biostudies-other | 2017 Jan

REPOSITORIES: biostudies-other

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Stereocontrolled Formation of a [4.4]Heterospiro Ring System with Unexpected Inversion of Configuration at the Spirocenter.

Ma Zhiqiang Z You Lin L Chen Chuo C

The Journal of organic chemistry 20161220 1

Stereoselective construction of the 1,3-diazaspiro[4.4]nonane core skeleton of massadine and related dimeric pyrrole-imidazole alkaloids is a synthetic challenge. We describe herein the synthesis of all C13/14 diastereomers of this spiro molecule through controlled oxidation and epimerization of the C13 spirocenter under mild acidic conditions. ...[more]

PMID: 27933858

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