申请人:Bayer Aktiengesellschaft
公开号:US03993665A1
公开(公告)日:1976-11-23
3-Amidocoumaranones which may be substituted in the benzene ring by halo or alkyl; the compounds are obtained by treating an appropriate 2-hydroxyphenylacetic acid lactone with nitrous acid or with an ester, salt or chloride of nitrous acid in an acid medium to afford a coumaranedione-3-monoxime which is subjected to catalytic hydrogenation in the presence of an acid anhydride. The resulting 3-amidocoumaranone is an intermediate in the preparation of .alpha.-amino-2-hydroxyphenylacetic acid which can be used to synthesize antibiotics such as cephalosporin and penicillin derivatives.
3-氨基香豆素酮可以在苯环上被卤素或烷基取代;这些化合物是通过用亚硝酸或亚硝酸酯、盐或氯化物处理适当的2-羟基苯乙酸内酯在酸性介质中得到的,从而得到一种香豆二酮-3-一氧化物,该一氧化物在酸酐存在下进行催化氢化。所得的3-氨基香豆素酮是合成α-氨基-2-羟基苯乙酸的中间体,可用于合成头孢菌素和青霉素衍生物等抗生素。