Synthesis, Characterization and Biological Evaluation of Schiff's bases containing Indazole Moiety

Indazole containing derivatives represent one of the most important heterocycles in pharmaceuticals. Substituted indazole derivatives bear a variety of functional groups and display versatile biological activities. A series of new Indazolyl derivatives have been prepared from commercially available N-substituted-3-indazole carboxylic acid and methanol with sulphuric acid. Synthesis of these compounds proceeds through the formation of 1-ethyl-1H-indazole -3-carboxylate, by acidic esterification, then conveted in to 1-ethyl-1H-indazole -3-hydrazide using hyrdazine hydrate in ethanol at reflux temperature. Then 1-ethyl-1H-indazole-3-hydrazide was condensed with different substituted benazadehydes using catalytic amount of conc. sulphuric acid in ethanol. Some of the synthesized derivatives were then evaluated for antibacterial activity against different bacterial strains which shows good Antibacterial activities.