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Regioselective alcoholysis of silychristin acetates catalyzed by lipases.

ABSTRACT: A panel of lipases was screened for the selective acetylation and alcoholysis of silychristin and silychristin peracetate, respectively. Acetylation at primary alcoholic group (C-22) of silychristin was accomplished by lipase PS (Pseudomonas cepacia) immobilized on diatomite using vinyl acetate as an acetyl donor, whereas selective deacetylation of 22-O-acetyl silychristin was accomplished by Novozym 435 in methyl tert-butyl ether/ n-butanol. Both of these reactions occurred without diastereomeric discrimination of silychristin A and B. Both of these enzymes were found to be capable to regioselective deacetylation of hexaacetyl silychristin to afford penta-, tetra- and tri-acetyl derivatives, which could be obtained as pure synthons for further selective modifications of the parent molecule.

SUBMITTER: Vavrikova E

PROVIDER: S-EPMC4490424 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Regioselective alcoholysis of silychristin acetates catalyzed by lipases.

Vavříková Eva E Gavezzotti Paolo P Purchartová Kateřina K Fuksová Kateřina K Biedermann David D Kuzma Marek M Riva Sergio S Křen Vladimír V

International journal of molecular sciences 20150526 6

A panel of lipases was screened for the selective acetylation and alcoholysis of silychristin and silychristin peracetate, respectively. Acetylation at primary alcoholic group (C-22) of silychristin was accomplished by lipase PS (Pseudomonas cepacia) immobilized on diatomite using vinyl acetate as an acetyl donor, whereas selective deacetylation of 22-O-acetyl silychristin was accomplished by Novozym 435 in methyl tert-butyl ether/ n-butanol. Both of these reactions occurred without diastereomer ...[more]

PMID: 26016503

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