发明名称 |
SYNTHESIS OF 4 alpha -ARYLEPICATECHINS |
摘要 |
Oligomeric procyanidins containing 4 alpha -linked epicatechin units are in nature and have hitherto not been accessible through stereoselective synthesis. Provided herein is the preparation of the prototypical dimer, epicatechin-4 alpha ,8-epicatechin, by reaction of the protected 4-ketones with aryllithium reagents derived by halogen/metal exchange from the aryl bromides. Removal of the 4-hydroxyl group from the resulting tertiary benzylic alcohols is effected by tri-<i>n</i>-butyltin hydride and trifluoroacetic acid in a completely stereoselective manner, resulting in hydride delivery exclusively from the beta face. |
申请公布号 |
WO0220506(A2) |
申请公布日期 |
2002.03.14 |
申请号 |
WO2001US26175 |
申请日期 |
2001.08.21 |
申请人 |
MARS, INC. |
发明人 |
KOZIKOWSKI, ALAN, P.;ROMANCZYK, LEO, J., JR.;TUECKMANTEL, WERNER |
分类号 |
C07D311/62;C07F7/18 |
主分类号 |
C07D311/62 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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