ethyl 4,5,6,7-tetrahydro-1H-indole-2-carboxylate

ethyl 5-methoxyimidazo[1,2-a]quinoline-2-carboxylate

ethyl 2-hydrazinyl-1,3-thiazole-4-carboxylate

ethyl 2-(2-benzylidenehydrazinyl)-1,3-thiazole-4-carboxylate

ethyl 5-methyl-3-nitroimidazo[1,2-a]pyridine-2-carboxylate