A method of producing a 4-halo-2-(substituted or unsubstituted)hydroxyimino-3-oxobutyric acid ester or amide, which is a synthetic intermediate of value for the production of cephalosporins containing an aminothiazole group, characterized by reacting a 2-(substituted or unsubstituted)-hydroxyimino-3-oxobutyric acid or an ester or amide thereof with a silylating agent and reacting the resulting novel 2-(substituted)hydroxyimino-3-silyloxy-3-butenoic acid ester or amide with a halogenating agent.
一种制备4-卤代-2-(取代或未取代)羟基
亚胺-3-酮
丁酸酯或酰胺的方法,该方法是制备含有
氨基
噻唑基团
头孢菌素的合成中间体,其特征在于将2-(取代或未取代)羟基
亚胺-3-酮
丁酸或其酯或酰胺与
硅烷化试剂反应,并将所得的新型2-(取代)羟基
亚胺-3-
硅氧基-3-
丁烯酸酯或酰胺与卤代试剂反应。