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Synthesis of docetaxel and butitaxel analogues through kinetic resolution of racemic beta-lactams with 7-O-triethylsilylbaccatin III.

ABSTRACT: The kinetic resolution of racemic cis-4-phenyl- and cis-4-tert-butyl-3-hydroxy-beta-lactam derivatives with 7-O-triethylsilylbaccatin III yielded paclitaxel and butitaxel analogues with high diastereoselectivity. The results demonstrated that the tert-butyldimethylsilyl protecting group at the C3-hydroxy group of the beta-lactams provided optimum kinetic resolution in comparison with the sterically less demanding triethylsilyl group and the larger triisopropylsilyl group. In addition, it was found that the C4 beta-lactam substituents also influenced diastereoselectivity. The C4 tert-butyl-beta-lactams provided better diastereoselectivity than the corresponding C4 phenyl beta-lactams.

SUBMITTER: Ge H

PROVIDER: S-EPMC2596597 | biostudies-literature | 2007 Feb

REPOSITORIES: biostudies-literature

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Synthesis of docetaxel and butitaxel analogues through kinetic resolution of racemic beta-lactams with 7-O-triethylsilylbaccatin III.

Ge Haibo H Spletstoser Jared T JT Yang Yan Y Kayser Margaret M Georg Gunda I GI

The Journal of organic chemistry 20070201 3

The kinetic resolution of racemic cis-4-phenyl- and cis-4-tert-butyl-3-hydroxy-beta-lactam derivatives with 7-O-triethylsilylbaccatin III yielded paclitaxel and butitaxel analogues with high diastereoselectivity. The results demonstrated that the tert-butyldimethylsilyl protecting group at the C3-hydroxy group of the beta-lactams provided optimum kinetic resolution in comparison with the sterically less demanding triethylsilyl group and the larger triisopropylsilyl group. In addition, it was fou ...[more]

PMID: 17253791

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