Abstract
4-(Aryl)-6-pyridin-3-yl-1H-pyrazolo[3,4-b]pyridin-3-amines were reacted with dimethylformamide-dimethylacetal to give the corresponding pyrazolopyridin-3-yl-imidoformamides which in turn, reacted with malononitrile or 2-cyanoethanethioamide and ethyl cyanoacetate to give the corresponding pyridopyrazolo-pyrimidines. Also, they reacted with active halogen-containing compounds to give the corresponding imidazopyrazolopyridin-2-amines and pyrazolopyridin-2-yl-1-aryl-ethanones. The structures of all newly synthesized heterocyclic compounds were elucidated by considering the data of elemental analyses, IR, 1H NMR and mass spectrometry. All newly synthesized heterocyclic compounds were tested as anti-Alzheimer and anti COX-2 reagents and exhibited promising results.
Keywords: Pyrazolopyridin-3-ylimidoformamides, Pyridopyrazolopyrimidines, Imidazopyrazolopyridin-2-amines, Pyrazolopyridin-2-yl-1-arylethanones, Phenyl-3-(substituted)-1H-pyrazolopyridin-3-yl]thiourea, dimethylformamide-dimethylacetal, 4-(aryl)-6-pyridin-3-yl-1Hpyrazolo[3,4-b]-pyridin-3-amines, N,N-dimethyl-N'-[4-phenyl-6-(pyridin-3-yl)-1H-pyrazolo [3,4-b]pyridin-3-yl]imidoformamide, 2-bromo-1-(aryl)ethanones, dimethylformamide, dehydrobromination, N-1 alkyl derivatives, Anti-COX2, N,N-Dimethyl-N'-(4-phenyl-6-pyridin-3-yl-1H-pyrazolo[3,4-b]pyridine-3-yl)imidoformamide (3a), N'-[4-(4-Methoxyphenyl)-6-pyridin-3-yl-1H-pyrazolo[3,4-b]pyridin-3-yl]-N,N-dimethylimidoformamide (3b), 4-Amino-10-phenyl-8-pyridin-3-ylpyrido[2',3':3,4]pyrazolo [1,5-a] pyrimidine-3-carbonitrile, 4-Amino-10-(4-Methoxyphenyl)-8-pyridin-3-ylpyrido[2',3':3,4] pyrazolo[1,5-a]pyramidine-3-carbonitrile, Ethyl-4-amino-10-phenyl-8-pyridin-3-ylpyrido[2',3':3,4]pyrazolo[1,5-a]pyramidine-3-carboxylate, 9-Phenyl-7-pyridin-3-yl-3H-imidazo[1',2':1,5]pyrazolo[3,4-b]pyridin-2-amine, 9-(4-Methoxyphenyl)-7-pyridin-3-yl-3H-imidazo[1',2':1,5] pyrazolo[3,4-b]pyridin-2-amine, N'-(9-(4-Methoxyphenyl)-7-pyridin-3-yl-3H-imidazo[1',2':1, 5]pyrazolo[3,4-b]pyridin-2-yl)-N,N-dimethylimidoformamide, 2-(3-Amino-4-Phenyl-6-pyridin-3-yl-2H-pyrazolo[3,4-b]pyridin-2-yl)-1-(4-chloro-phenyl)ethanone, 2-(3-Amino-4-(4-methoxyphenyl)-6-pyridin-3-yl-2H-pyrazolo[3,4-b]-pyridin-2-yl)-1-phenylethanone, 2-(3-Amino-4-(4-Methoxyphenyl)-6-pyridin-3-yl-2H-pyrazolo[3,4-b]-pyridin-2-yl)-1-(4-chlorophenyl)ethanone, N-[4-(4-Methoxyphenyl)-2-(2-oxo-2-phenylethyl)-6-pyridin-3-yl-2H-pyrazolo[3,4-b]pyridin-3-yl]acetamide, 1-(4-(4-Methoxyphenyl)-6-pyridin-3-yl-1H-pyrazolo[3,4-b]pyridin-3-yl)-3-phen-ylthiourea, 4-(4-Methoxyphenyl)-N-[4-methyl-3-phenyl-1,3-thiazol-2(3H)-ylidene]-6-pyridin-3-yl-1H-pyrazolo[3,4-b]pyridin-3-amine, N-[4-(4-Chlorophenyl)-3-Phenyl-1,3-thiazol-2(3H)-ylidene]-6-pyridin-3yl-4-(4-methoxyphenyl)-1H-pyrazolo[3,4-b]pyridin-3-amine, 1-{2-[(4(4-Methoxyphenyl)-6-pyridin-3yl-1H-pyrazolo[3,4-b]pyridin-3-yl)imino]-5-methyl-3-phenyl-2,3-dihydro-1,3-thiazol-4-yl}ethanone (25b), prostaglandin H2 synthase-1, R-flurbiprofen-supplemented chow adlibitum