Enaminones in Heterocyclic Syntheses: Part 4. A New One-Step Synthetic Route to Pyrrolo[3,4-b]pyridine and Convenient Syntheses of 1,4-Dihydropyridines and 1,1′-(1,4-Phenylene)bis(1,4-dihydropyridine)

Reactions of cyano olefins with (i) enamino imides afforded novel pyrrolo[3,4-b]pyridines; (ii) enamino esters afforded new 1,4-dihydropyridines; and (iii) bisenamino ester afforded new 1,1′-(1,4-phenylene)bis(1,4-dihydropyridine). The new derivatives are planned as suggested drug candidates.