Synthesis and antitumor activity of some new pyrazolo[3,4-d]pyrimidine and pyrazolo[3,4-b]pyridine derivatives

A new series of pyrazolo[3,4-d]pyrimidine-3-carbonitrile and pyrazolo[3,4-b]pyridine-3- carbonitrile derivatives was synthesized by the reaction of 5-amino-1-tosyl-1H-pyrazole- 3,4-dicarbonitrile as a key starting material with various electrophilic and nucleophilic reagents. All the newly synthesized compounds were structurally confirmed by various modern analytical methods (IR, 1H NMR and MS). All the title compounds have been evaluated for their potential cytotoxicity against human laryngeal epidermoid carcinoma cells (Hep2). Among the screened compounds, 3 and 4 exhibited the highest significant effect.