重氮甲烷 、
5-(4-Chloro-benzoyl)-6-imino-3-methyl-5,6-dihydro-pyrazolo[5,1-b]thiazole-2,7-dicarboxylic acid 2-ethyl ester 7-methyl ester 以
1,4-二氧六环 、
乙醚 为溶剂,
以96%的产率得到5-(4-Chloro-benzoyl)-3-methyl-6-[(E)-methylimino]-5,6-dihydro-pyrazolo[5,1-b]thiazole-2,7-dicarboxylic acid 2-ethyl ester 7-methyl ester