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.
WileyR. H. and JarboeC. H., The Chemistry of Heterocyclic Compounds, Interscience Publishers, New York, 1967, vol. 22, part 2, p. 183.
3.
ShibaS. A., HarbN. M. S., HassanM. A., El-KassabyM. A. and Abou-El RegalM. M. K., Indian J. Chem., Sect. B: Org. Chem. Incl. Med. Chem., 1996, 35, 426.
4.
ElnagdiM. H., ElmoghayarM. R. H. and ElghandourA. H., Sulfur Lett., 1989, 9, 109.
