Synyhesis Of Fused Heterocycles With Biological Activiyies

Condensation of4-amino-3-aryl-5-mercapto-1,2,4-trizole with4-chloro pyridine-3-carboxylic acid or its derivatives in the presence of phosphorus oxychloride gave5novel3-aryl-6-(substituted-4-chloropyridine-3-yl)-s-triazo lo[3,4-b]-1,3,4-tinadiazoles and2novel3-aryl-6-(substituted-4-hydroxypyri dine-3-yl)-s-triazolo[3,4-b]-1,3,4-tinadiazoles. The hydrazinolysis of3-aryl-6-(substituted-4-chloropyridine-3-yl)-s-triazolo[3,4-b]-1,3,4-tinadiazoles gave2novel3-amino-1H-triazolo[4,3-c]pyridines and1novel1,2-dihydro-tria zolo[4,3-c]pyridine-3-one. The structures of the compounds synthesized were determined by1H NMR, IR and MS spectra. Their spectral properties and the reaction mechanism were also discussed. It offers an efficient, rapid and high yield method to prepare triazolo[4,3-c]pyridine derivatives, and a possible mechanism is also suggested.We synthesized43interim compounds, such as ethyl benzoate derivatives, benzoyl hydrazine derivatives,2-mercapto-5-subtituedphenyl-1,3,4-oxa diazole derivatives,2-methylthioether-5-subtituedphenyl-1,3,4-oxadiazole derivatives,2-mesyl-5-subtituedphenyl-1,3,4-oxadiazole derivatives,2-diazanyl-5-subtitued phenyl-1,3,4-oxadiazole derivatives and ethyl4-chloro quinoline-3-carboxylate, and7novel2-(5-(phenyl)-1,3,4-oxadiazole)-3H-triazolo[4,3-c]quinoline derivatives. Their structures were not identified.Using D, L-alanine and2-ethoybenzamidine hydrochloride as stocks, Vardenafil was synthesized by multi-reaction, such as acylation, nucleophilic addition, nucleophilic substitution, condensation, sulfonation, alkalization, etc. The structure of Vardenafil was determined by1H NMR and MS spectra while the structures of interim compounds were determined by MS spectra. It offers a new method to prepare Vardenafil, which is operational simple, easy to separate, high yield but low cost. It also optimizes the synthesis routine, reduces the reaction difficulty and favors the industrial production.