Several new pyrazolo[3,4-b]pyridines 7a,b were prepared  via reacting compound  1,5-dimethyl-4-nitroso-2-phenyl-1H-pyrazol-3(2H)-one 1 with the arylmethylenemalononitriles 3 .The reaction of 4-(aryldiazenyl)-1H-pyrazole-3,5-diamines 2 with arylmethylenemalononitriles 3a,b ,ethoxymethylenemalononitrile 3d and  2-(1H-benzo[d]imidazol-2-yl) -3-(dimethylamino)acrylonitrile  12 resulted in the formation of pyrazolo [1,5-a]pyrimidine derivatives 8,10 and 15 respectivily.