L-Proline Catalyzed Synthesis of Structurally Diverse 1,4- dihydropyridines Fused with Medicinally Privileged Heterocyclic Systems

Structurally diverse unsymmetrically annulated 1,4-dihydropyridines have been synthesized by L-proline catalyzed four-component domino protocol involving the reaction of 2-aminobenzothiazole, thiophene-2-carbaldehyde and carbonyl compounds in ethanol. The utilization of L-proline in the multicomponent reaction will make the present protocol attractive for synthesis of 1,4-dihydropyridines in terms of reaction efficiency, atom-economy and environmental safety.