Selenium-Containing Heterocycles: Synthetic investigation of some new series 3-(5-mercapto-1,3,4-oxadiazol-2-yl)-2H-selenopyrano[2,3-b]quinolin-2-ones

Abstract A Series of hybrid 3-(5-mercapto-1,3,4-oxadiazol-2-yl)-2H-selenopyrano[2,3-b]quinolin-2-one derivatives (3a-f) were synthesized by the reaction of 2-oxo-2H-selenopyrano[2,3-b]quinoline-3-carbohydrazides (2a-f) with carbon disulphide and potassium hydroxide in the presence of ethanol as solvent. The intermediates 2-oxo-2H-selenopyrano[2,3-b]quinoline-3-carbohydrazides (2a-f) were obtained by the reaction of 2-oxo-2H-selenopyrano[2,3-b]quinoline-3-carboxylates (1a-f) with hydrazine hydrate in ethanol. These (1a-f) were synthesized from available literature method. All the newly synthesized derivatives have been characterized by IR, 1H NMR, 13C NMR spectral and elemental analysis.