发明名称 |
Process for the preparation of chiral 4-aryloxyazetidinones |
摘要 |
A process for preparing a single enantiomer of a 4-aryloxyazetidin-2-one derivative in optically pure form comprises reacting a hindered vinyl ester with chlorosulphonyl isocyanate; displacing the hindered acyloxy group with a phenolic derivative containing a protected carboxy group; deprotecting the carboxylate moiety; resolving with a chiral amine; filtering; and regenerating the desired enantiomer by acidification. A method for enriching the product obtained from the acyloxy displacement step in favour of the desired enantiomeric form, by treating with an asymmetric catalyst such as a chiral alkaloid derivative, is provided; as also is a method for racemising the unwanted antipode of the desired 4-aryloxyazetidin-2-one enantiomer. The invention further provides novel enantiomers based on the 4-aryloxyazetidin-2-one ring structure.
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申请公布号 |
US5310899(A) |
申请公布日期 |
1994.05.10 |
申请号 |
US19930020518 |
申请日期 |
1993.02.22 |
申请人 |
MERCK SHARPE & DOHME LTD. |
发明人 |
ASHWOOD, MICHAEL S.;BISHOP, BRIAN C.;HOUGHTON, PETER G.;HUMPHREY, GUY R. |
分类号 |
C07D205/08;(IPC1-7):C07B53/00;C07B55/00 |
主分类号 |
C07D205/08 |
代理机构 |
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主权项 |
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地址 |
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