pyrimidine, pyrazolopyridine and pyranopyrazole derivatives

activities. They are also effective as antiplatelet agents with analgesic activity (10) and as a new drug for treatment of insomnia (11). In view of these reports and as continuation of our recent studies (12, 13), the syn-theses of a new series of compounds containing the pyrimidine moiety are now repor-ted. The one-pot reaction of 2-(2,4-dinitrophenyl)-5-methyl-2,4-dihydro-3H-pyrazol-3-one (1), p-methoxybenzaldehyde, malononitrile in the presence of ammonium acetate or piperidine afforded the bifunctional compounds 2 and 3, which are used as key interme-diates for the preparation of pyrimidine derivatives in their reactions with formic acid, formamide-formic acid-dimethylformamide, ammonium thiocyanate in acetic acid and triethyl orthoformate, followed by cyclization with hydrazine hydrate. Several com-pounds were screened for their antimicrobial activity