Synthesis of derivatives of pyrano[3,4-c][1,2,4]triazolo-[4,3-a]pyridine and 8-(pyrazol-1-yl)pyrano[3,4-c]pyridine through pyridine ring rearrangement

Abstract

A method has been developed for the synthesis of 8-hydrazino derivatives of pyrano[3,4-c]pyridines on the basis of pyridine ring recyclization. New tricyclic heterocyclic systems, pyrano[3,4-c][1,2,4]triazolo[4,3-a]pyridines and 8-(pyrazol-1-yl)pyrano[3,4-c]pyridines, were synthesized from 8-hydrazino derivatives of pyrano[3,4-c]pyridines. The presence of intermolecular hydrogen bonds in 6-[(4-chlorophenyl)amino]-8-(3,5-dimethyl-1H-pyrazol-1-yl)-3,3-dimethyl-3,4-dihydro-1H-pyrano[3,4-c]pyridine-5-carbonitrile was proved by X-ray structural analysis. The antimicrobial and antitumor activity of the obtained compounds were studied.