Facile synthesis of fused nitrogen containing heterocycles as anticancer agents

One pot three components reaction of the pyrazol-5-one 1 with different aromatic aldehydes and malononitrile was carried out in the presence of Ammonium acetate to furnish the corresponding pyrazolopyridines 2a-g. Carrying out the same reactions in the presence of piperydine yielded the pyranopyrazoles 4a-c. Facile formation of the pyrazolopyridopyrimidines 5a-c and 6a,b was occurred via boiling of the adducts 2a,b,e in Formic acid or chloroacetic acid. Treatment of adduct 2a with triethyl orthoformat yielded the pyrazolopyrrolopyridine derivative 7. Compound 2a was also reacted with DMFDMA to form the corresponding adduct 8. Pyrazol-5-one 1 underwent three different component reactions using a variety of active methylene reagents. The utility ethylbenzoyl acetate and benzoyl acetonitrile yielded the products 9a-e and 10 respectively. Using of ethylacetoacetate and ethyl cyano acetate reagents led to the formation of adducts 11 and 12a-c, respectively. On the other hand, diethylmalonate and acetylacetone produced the corresponding products 13 and 14. The bioactivity of the compounds (2c, 2e, 2d, 4a, 4b, 9c, 9e, 11, 12b, 12c) as antitumor agents against liver carcinoma was examined.