8-cyclopropyl-2-ethylsulfanyl-5-oxo-5,8-dihydro-pyrido[2,3-d]pyrimidine-6-carboxylic acid 、
N-甲基哌嗪 在
乙醇 作用下,
以
N-dimethylformamide 为溶剂,
反应 2.5h,
以2.4 g (73% of the theoretical yield) of 2-(4-methyl-piperazino-8-cyclopropyl-5-oxo-5,8-dihydro-pyrido[2,3-d]pyrimidine-6-carboxylic acid with a melting point of 209°-210° C.的产率得到4-Methyl-piperazino-8-cyclopropyl-5-oxo-5,8-dihydro-pyrido[2,3-d]pyrimidine-6-carboxylic acid