76182-22-4Relevant academic research and scientific papers
Purines, Pyrimidines, and Imidazoles. Part 58. Synthesis and Reactions of some Imidazole-2,4-dicarboxylic Acid Derivatives
Brown, Tom,Shaw, Gordon,Durant, Graham J.
, p. 809 - 812 (2007/10/02)
Diethyl 5-amino-1-(p-methoxybenzyl)imidazole-2,4-dicarboxylate (3b) has been prepared from ethyl 2-amino-2-cyanoacetate and ethyl 1-ethoxycarbonylformimidate hydrochloride or ethyl triethoxyacetate followed by reaction with p-methoxybenzylamine.The diester, with one equivalent of dilute sodium hydroxide solution, furnished ethyl 5-amino-1-(p-methoxybenzyl)imidazole-4-carboxylate (7a).Diazotisation of the diester (3b) and reaction of the diazonium salt with copper(I) chloride produced diethyl 5-chloro-1-(p-methoxybenzyl)imidazole-2,4-dicarboxylate (9a) which, with dilute alkali, gave ethyl 5-chloro-1-(p-methoxybenzyl)imidazole-4-carboxylate (7b).Diazotisation of the diester (3b) in the presence of hypophosphorous acid gave diethyl-1-(p-methoxybenzyl)imidazole-2,4-carboxylate (9b) which, when hydrogenated over palladium-charcoal, produced diethyl imidazole-2,4-dicarboxylate (9c).This with bromine (chlorine) gave diethyl 5-bromo(chloro)imidazole-2,4-dicarboxylate (9d and e).The chloro derivative (9a) was similarly hydrogenated using palladium-charcoal to produce diethyl 5-chloroimidazole-2,4-dicarboxylate (9e).
Purines, Pyrimidines, and Imidazoles. Part 53. Synthesis of Some 5-Halogeno-analogues of Metiamide and Cimetidine
Brown, Tom,Shaw, Gordon,Durant, Graham J.
, p. 2310 - 2315 (2007/10/02)
Ethyl 5-chloroimidazole-4-carboxylate has been prepared by diazotisation of ethyl 5-amino-1-(di-O-isopropylidene-α- or α,β-D-mannofuranosyl)imidazole-4-carboxylate, reaction of the diazonium salt with copper(I) chloride and removal of the 1-substituent with hydrochloric acid, or by similar conversion of ethyl 5-amino-1-t-butylimidazole-4-carboxylate to ethyl 1-t-butyl-5-chloroimidazole-4-carboxylate, and removal of the t-butyl group with hydrogen bromide.Ethyl 5-fluoroimidazole-4-carboxylate has been prepared from ethyl 5-amino-1-t-butylimidazole-4-carboxylate by diazotisation and photolysis in the presence of tetrafluoroboric acid.Ethyl 5-chloroimidazole-4-carboxylate and ethyl 5-fluoroimidazole-4-carboxylate have been converted into the corresponding alcohols by reaction with lithium aluminium hydride. 5-Chloro-4-(hydroxymethyl)imidazole has also been prepared by electrolysis of 5-chloroimidazole-4-carboxylic acid at mercury cathode. 5-Chloroimidazole has been converted into the 5-chloroimidazolyl analogues of metiamide and cimetidine by a sequence of reactions, and 5-fluoroimidazole has been similarly converted into the 5-fluoro-analogue of metiamide.The metiamide and cimetidine analogues were found to be histamine H2-receptor antagonists.
