Der Pharma Chemica
Journal for Medicinal Chemistry, Pharmaceutical Chemistry, Pharmaceutical Sciences and Computational Chemistry


Novel 4-(substituted) pyrazolyl 5,6-dipyridylpyridazin-3(2H)-ones likely to possess antihypertensive and anti-inflammatory activities

Author(s): Amal F. Seliem

Cyclocondensation of pyridilmonohydrazone and ethyl acetoacetate in refluxing sodium ethoxide/ethanol solution afforded 4-acetyl-5,6-dipyridylpyridazin-3(2H)-one 3 which on reaction with diethyl oxalate in refluxing sodium ethoxide/ethanol mixture gave ethyl 2,4-dioxo-4- (3-oxo-5,6- dipyridyl -2,3-dihydropyridazin4-yl) butanoate 4. While on reaction of butanoate 4 with hydrazine hydrate in refluxing ethanol afforded ethyl 5-(3-oxo -5,6-dipyridyl -2,3-dihydro pyridazin 4-yl)-1H-pyrazole-3-carboxylate 5. Reaction of the ester 4 with hydrazine hydrate in refluxing ethanol gave the acid hydrazide 6 .Hydrazide derivative 6 was considered as intermediate for synthesis different heterocyclic moieties attached to pyridazinones nucleus such as pyrazoles ,oxadiazoles,amino pyrazolones and methyl pyrazolone derivatives 12, 13,14 and 16 . The structure of all newly synthesized was confirmed from analytical and spectral data.