Mohamed S. A. El-Gaby,

Department of Chemistry, Faculty of Science, Al–Azhar University at Assiut, Assiut 71524, Egypt

Nadia M. Taha, Jehane A. Micky
Department of Chemistry, Faculty of Science (Girl’s), Al–Azhar University, Nasr City, Cairo, Egypt.

Marwa A. M. Sh. El-Sharief
 

ABSTRACT

Various sulfa drugs were coupled with active methylene compounds to give various hydrazones  2a-e. The reactivity of hydrazones 2a-e towards hydrazines was investigated. Thus , a novel series of 3, 5– diaminopyrazoles 3, 5, 6, 7a, and b and 9a, b were obtained  by treatment of 2 with hydrazines. Pyrazolo[1,5-a][1,3,5] triazine derivatives 10, 11 and 12 were synthesized by interaction of aminopyra-zole 9a with triethyl  orthoformate, acetic anhydride and benzoyl chloride , respectively. When aminopyrazole 6 and 8 were allowed to react with ketene  dithioacetal  13, the novel pyrazolo[1,5-a] pyrimidine 15a,b were obtained. Structures of the new compounds were established by their elemental analysis and spectral data. Some of the synthesized compounds were tested in vitro for their antimicrobial activity.