Ethyl 2-diazoacetoacetate

Abstract

Cunha and co-workers showed that ethyl 2-diazoacetoacetate undergoes reaction with different phenylhydrazine hydrochlorides (route I) or arylsulfonylhydrazides (route II) to yield the corresponding 1,2,3-triazole derivatives in good yield. The intramolecular 1,5- electrocyclization of β-substituted-α-diazocarbonyl compounds represents an efficient and flexible method for preparing various substituted 1,2,3-triazoles from easily available, properly functionalized carbonyl compounds and amine derivatives. The N-amino triazoles are easily converted into the corresponding 5-methyl-1H-[1,2,3]-triazole-4-carboxylic acid hydrazides, that exhibited in vitro antiplatelet profile against human platelet aggregation using arachidonic acid, adrenaline and ADP as agonists.5 The 1-arylsulfonylamino-5- methyl-1H-[1,2,3]-triazole-4-carboxylic acid ethyl esters were able to neutralize the hemolytic property of L. muta crude venom. © Georg Thieme Verlag Stuttgart. New York.