| 摘要 |
<p>NEW MATERIAL:A compound of formula I [R1 is an OH-protecting group of formula II (R5-R7 are 1-4C alkyl); R2-R4 are 1-4C alkyl, phenyl or aralkyl]. EXAMPLE:(3R,4R,5R)-3-(1-tert-butyldimethylsilyloxyethyl)-4-trimethyl silyloxyazetidine-2-one. USE:An intermediate for synthesizing carbapenem beta-lactam compounds. PREPARATION:An enolsilyl ether of formula III [e.g., (3R)-3-tert-butyldimethyl silyloxy-bute-1-nyltrimethylsilyl ether] is reacted with chlorosulfonyl isocyanate and subsequently reduced.</p> |
