A. M. Shalaby, O. A. Fathalla, E. M. M. Kassem, and M. E. A. Zaki
National Research Centre, Dokki, Cairo, Egypt
e-mail : mzaki@nrc.sci.eg

ABSTRACT

Reaction of ketene derivatives (1a,b) on treatment with 4-amino-1-phenyl-2,3-dimethyl pyrazolin-5-one gives compounds (2a,b) which react with hydrazine to afford 1-phenyl- 2,3 dimethyl-4-[3-(5-amino-4-substituted)-1H-pyrazolylamino]pyrazolin-5-one (3a,b).
 Compounds (3a,b) on treatment with Boc. amino acids derivatives, acetic anhydride, ethyl acetoacetate and aldehydes afforded (4a-h), (5a-h), (6-10), (11a,b), respectively. Interaction of (9) or (10) with acetohydrazide, hydrazines, and then with p-bromobenzaldehyde afforded compounds (13), (14a,b) and (15), respectively. Interaction of (3a) with thioglycollic acid afforded pyrazolopyridines derivatives (16).