New Routes for Novel Pyrazolo[3,4-b][1,6]-naphthyridine, Pyrazolo[3,4-b]pyridine and Pyrazolo[3,4:2,3]pyrido[6,1-a]benzimidazole Derivatives

Abstract

Pyrazolo[3,4-b][1,6]naphthyridine, pyrazolo[3,4-b]pyridine and pyrazolo[3,4:2,3]pyrido[6,1-a]benzimidazole derivatives are synthesized starting from the isomeric 3-substituted 5-chloro-1-phenylpyrazole-4-carbaldehyde.