A 2'-halopenicillin compound is prepared from a penicillin-1-oxide compound by the action of an acid halide in the presence of a base. The product on heating rearranges to a 3-halo-3-methylcepham compound which itself gives a 3-methyl-3-cephem compound on further heating. A 2'-halopenicillin compound gives a 3-methyl-3-cephem compound on heating. The 2'-halopenicillin compounds, 3-halo-3-methylcepham compound and 3-methyl-3-cephem compounds are antibacterials which are also useful as intermediates for the synthesis of other penicillins and cephalosporins.
                            一种2'-卤代
青霉素化合物是通过在碱的存在下用酸卤化物作用于
青霉素-1-氧化物化合物来制备的。在加热后,产物重排成为3-卤代-3-甲基头孢烷化合物,进一步加热会生成3-甲基-3-头孢烯化合物。2'-卤代
青霉素化合物在加热后会生成3-甲基-3-头孢烯化合物。2'-卤代
青霉素化合物,3-卤代-3-甲基头孢烷化合物和3-甲基-3-头孢烯化合物是抗菌剂,也可用作合成其他
青霉素和
头孢菌素的中间体。