Routes to pyrazolo[3,4-e][1,4]thiazepine, pyrazolo[1,5-a]pyrimidine and pyrazole derivatives

摘要

5-Aminopyrazole 1 was condensed with aryl aldehydes to give the 4-arylidenes 2. Compound 2 reacted with thioglycolic acid and ethyl cyanoacetate to give the pyrazolothiazepines 3 and pyrazolopyrimidines 4, respectively. Diazotized 2a coupled with resorcinol to give the pyrazole derivative 5a. Reaction of la with P-keto esters 7, 8 and acetoacetanilides 13 afforded the pyrazolopyrimidines 11, 12 and 15, respectively. Condensation of la with 2-acetylindan-1,3-dione 16 yielded fused pyrazolopyrimidine 18. Compound 1a also reacted with the enaminonitriles 19 and 22 to give the pyrazolopyrimidine 20 and 24, respectively. [References: 8]