Compounds of formula
wherein R, and R, is each H, halo or an organic group, R3 is H or organic group, n = 1 or 2, M is a heavy mono- or divalent metal, or M2A wherein M2 is a heavy divalent metal and A is an organic or inorganic group, are prepared by treating a starting penicillin in a solvent with a salt of M, or M2A in the presence of a base at a temperature of from --70° to 100°C. The azetidinones of formula I are useful intermediates in the synthesis of β-lactam antibiotics, esp penem.
式 I 的氮杂
环丁酮化合物是合成 β-内酰胺类抗生素(尤其是青霉烯)的有用中间体,其中 R 和 R 分别为 H、卤素或有机基团,R3 为 H 或有机基团,n = 1 或 2,M 为一价或二价重
金属,或 M2A,其中 M2 为二价重
金属,A 为有机或无机基团。