申请人:Asahi Kasei Kogyo Kabushiki Kaisha
公开号:US04079180A1
公开(公告)日:1978-03-14
7-Aminocephalosporanic acid derivatives represented by the general formula (III), ##STR1## wherein X is hydrogen, hydroxyl, acetate or a nucleophilic residue, which are useful as a starting material for the synthesis of cephalosporin type antibiotics low in toxicity and broad in pharmacological effect can be easily prepared by allowing to react cephalosporin C or its derivative represented by the general formula (I), ##STR2## wherein X is as defined above, or a salt thereof with an .alpha.-keto derivative represented by the general formula (II), ##STR3## wherein R.sub.1 is carboxyl, aroyl or amide when R.sub.2 is hydrogen, and is carboxyl when R.sub.2 is alkyl or aryl, or its salt. In this case, the yield of the 7-aminocephalosporanic acid derivatives can be remarkably improved by carrying out the reaction in the presence of hydrogen peroxide. The yield can be further improved by adding thiosulfuric acid or a salt thereof after the completion of the reaction to decompose the unreacted hydrogen peroxide.
通式(III)所代表的7-氨基头孢菌素酸衍生物,其中X是氢、羟基、乙酸或亲核残基,可作为头孢菌素类抗生素的合成起始物质,其毒性低、药理效应广泛。该衍生物可通过让头孢菌素C或其通式(I)所代表的衍生物,其中X如上所定义,或其盐与α-酮衍生物通式(II)所代表的衍生物,其中R1为羧基、芳酰基或酰胺基,当R2为氢时,或当R2为烷基或芳基时为羧基,或其盐反应而制备。在这种情况下,通过在过氧化氢的存在下进行反应,可以显着提高7-氨基头孢菌素酸衍生物的产率。在反应完成后加入硫代硫酸或其盐以分解未反应的过氧化氢,可以进一步提高产率。