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Structure Revision of Poecillastrin C and the Absolute Configuration of the ?-Hydroxyaspartic Acid Residue.

ABSTRACT: The planar structure of poecillastrin C (1) was revised through selective reduction of the ester carbon. The absolute configuration of the ?-hydroxyaspartic acid (OHAsp) residue was determined to be d-threo by Marfey's analysis. The acid hydrolysate of the reduction product of 1 liberated (2R,3R)-2-amino-3,4-dihydroxybutanoic acid, demonstrating that the ?-carboxyl group in poecillastrin C was esterified. The structures of poecillastrins B-D and 73-deoxychondropsin A were also revised.

SUBMITTER: Irie R

PROVIDER: S-EPMC6325643 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Structure Revision of Poecillastrin C and the Absolute Configuration of the β-Hydroxyaspartic Acid Residue.

Irie Raku R Takada Kentaro K Ise Yuji Y Ohtsuka Susumu S Okada Shigeru S Gustafson Kirk R KR Matsunaga Shigeki S

Organic letters 20170928 19

The planar structure of poecillastrin C (1) was revised through selective reduction of the ester carbon. The absolute configuration of the β-hydroxyaspartic acid (OHAsp) residue was determined to be d-threo by Marfey's analysis. The acid hydrolysate of the reduction product of 1 liberated (2R,3R)-2-amino-3,4-dihydroxybutanoic acid, demonstrating that the β-carboxyl group in poecillastrin C was esterified. The structures of poecillastrins B-D and 73-deoxychondropsin A were also revised. ...[more]

PMID: 28956931

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