Some properties of 1-hydroxy-1H-imidazole-2-carboxylic acid esters

The corresponding amides and hydrazides were obtained by the reaction of 1-hydroxy-1H-imidazole-2-carboxylates with amines and hydrazine. In the reaction of an ester of 1-methoxy-4-methyl-5-(thiophen-2-yl)-1H-imidazole-2-carboxylic acid with NBS, bromination occurred at the thiophene ring, whereas in the reaction with 1,3-dibromo-5,5-dimethylhydantoin it took place at both the methyl group and the thiophene ring; its nitration led to mononitro- or dinitrothiophene derivatives. The reaction of 1-hydroxy-1H-imidazole-2-carboxylates with chloroacetone in Me₂CO in the presence of Et₃N resulted in the formation of reduced compounds.