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Stereoselective synthesis of four possible isomers of streptopyrrolidine.

ABSTRACT: The synthesis of (4R,5R)-streptopyrrolidine (1), (4S,5R)-streptopyrrolidine (2) (4R,5S)-streptopyrrolidine (3) and (4S,5S)-streptopyrrolidine (4) have been achieved in a concise and highly efficient manner via a highly stereoselective aldol type reaction with the trimethylsilyl enolate of ethyl acetate and Lewis acid mediated lactamization as the key reactions in ?42% yield over six steps starting from D-phenylalanine and L-phenylalanine, respectively. The absolute configuration of the natural product was shown to be (4S,5S) by comparing its spectral and analytical data with the reported values.

SUBMITTER: Mohapatra DK

PROVIDER: S-EPMC3028605 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Stereoselective synthesis of four possible isomers of streptopyrrolidine.

Mohapatra Debendra K DK Thirupathi Barla B Das Pragna P PP Yadav Jhillu S JS

Beilstein journal of organic chemistry 20110110

The synthesis of (4R,5R)-streptopyrrolidine (1), (4S,5R)-streptopyrrolidine (2) (4R,5S)-streptopyrrolidine (3) and (4S,5S)-streptopyrrolidine (4) have been achieved in a concise and highly efficient manner via a highly stereoselective aldol type reaction with the trimethylsilyl enolate of ethyl acetate and Lewis acid mediated lactamization as the key reactions in ≈42% yield over six steps starting from D-phenylalanine and L-phenylalanine, respectively. The absolute configuration of the natural p ...[more]

PMID: 21286392

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