Synthesis, reactions and characterization of 2-methylthionicotino-nitrile, pyrazolopyridine and pyridopyrazolotriazine derivatives

4,6-Diaryl-1H-pyrazolo[3,4-b]pyridin-3-amines 4a-c wereobtained in very pure state and used as the good startingmaterials for the present study. Compound 4a diazotized to give the corresponding diazonium salt 11 and also, reacted with 2-bromo-1-phenylethanone to give the corresponding pyrazolo[3,4-b]pyridin-2-yl)-1-phenylethanone derivative 7 which in turn, used for the preparation of the hydrazone and formamide derivatives 8 and 10 respectively through its reaction with hydrazine hydrate and formic acid respectively. Compound 11 was used for the preparation of pyridopyrazolotriazine derivatives via its coupling with several active –CH2- containing compounds.Considering the data from IR, 1H NMR, the mass spectra and elemental analyses the chemical structures of the newly synthesized heterocyclic compounds were elucidated