Cyclization Reactions of 5-Aminopyrazoles with β-Ketoesters, Enamines and β-Keto Anilides: New Synthetic Routes to Pyrazolo[1,5-a]Pyrimidine Derivatives
作者:F. M. A. El-Taweel、T. M. Abu Elmaati
DOI:10.1002/jccs.200200151
日期:2002.12
The pyrazolo[1,5-a]pyrimidines 4, 10, 11 and 14 were synthesized from reaction of 4-aryazo-2,5-diaminopyrazoles 1 with cyclic β-ketoesters 2a,b or cyclic β-ketoesters 7, 8 or acetoacetanilide 12, respectively. The reaction of 1 with the enamines 15, 16 and 17 yielded also the pyrazolo[1,5-a]pyrimidines 18, 20 and 21, respectively.