| 摘要 |
<p>NEW MATERIAL:A compound expressed by formula I (R1 is a protecting group of OH; R2-R4 are 1-4C alkyl, phenyl or aralkyl). EXAMPLE:( 3R,4R,5R )-3-( 1-tert-Butyldimethylsilyloxyethyl )-4-trimethylsilyloxyazetidin-2-one. USE:An intermediate for synthesizing carbapenem based beta-lactam compounds. PREPARATION:A enol silyl ether expressed by formula II, e.g. (3R)-3-tert-butyldimethylsilyloxy-buten-1-yltrimethylsilyl ether, is reacted with chlorosulfonyl isocyanate expressed by the formula ClSO2NCO, and the resultant product is then reduced with a reducing agent, preferably lithium aluminum hydride or bis-(2- methoxyethoxy)aluminum sodium hydride.</p> |
