41806-40-0Relevant articles and documents
Efficient synthesis of trisimidazole and glutaric acid bearing porphyrins: Ligands for active-site models of bacterial nitric oxide reductase
Collman, James P.,Yan, Yi-Long,Lei, Jianping,Dinolfo, Peter H.
, p. 923 - 926 (2007/10/03)
Ligands (1) for active-site models of bacterial nitric oxide reductase (NOR) have been efficiently synthesized. These compounds (1) feature three imidazolyl moieties and one carboxylic acid residue at the FeB site, which represent the closest available synthetic model ligands of NOR active center. The stereo conformations of these ligands are established on the basis of steric effects and 1H NMR chemical shifts under the ring current effect of the porphyrin.
Synthesis of xestomanzamines a and b
Burm, Brigitte E.A.,Blokker, Peter,Jongmans, Edwin,Van Kampen, Erwin,Wanner, Martin J.,Koomen, Gerrit-Jan
, p. 495 - 503 (2007/10/03)
Synthetic pathways are described for the synthesis of two naturally occurring β-carbolines, xestomanzamine A and B. The synthesis of aromatic xestomanzamine A was most conveniently achieved by way of a Grignard reaction in dichloromethane. This route is suitable for the synthesis of analogues with modifications in the imidazole ring of xestomanzamine A. Xestomanzamine B, an oxidation-sensitive dihydro-β-carboline, was prepared by Pictet-Spengler condensation of tryptamine with a vicinal tricarbonyl substituted imidazole.
A General Route to 4-Substituted Imidazoles
Katritzky, Alan R.,Slawinski, Jaroslaw J.,Brunner, Frederic,Gorun, Sergiu
, p. 1139 - 1145 (2007/10/02)
Literature routes to di(imidazol-4-yl)methanol (1a) dinitrate and tri(imidazol-4-yl)methanol (2a) trihydrochloride were improved to give 32 and 16percent overall yields, respectively; but we failed to synthesize bis- (1b) and tris-(1-methylimidazol-4-yl)methanol (2b) by the methylation of the corresponding N-methoxymethyl compounds (3; x=2 and x=3).Attempted 4-lithiation of the 1,2,5-protected imidazole (4a) with BuLi-TMEDA failed, giving after hydrolysis 1-methyl-5-trimethylsilylimidazole (4b); similar failures were observed for 2,5-dicarboxy-1-methylimidazole, which after metallation with BuLi-TMEDA and hydrolysis afforded 1-methylimidazole-5-carboxylic acid (5).Our attempts to obtain 4-bromo-1-methylimidazole (10a) and 4-bromo-1-ethylimidazole suitable for a halogen-lithium exchange or for Grignard reaction also failed.Attempted selective lithiation of 2-phenylthio-1-tritylimidazole (16) at the 4-position, then theatment with ethyl formate, led only to a mixture of 4- and 5-substituted products in very low yield, and 1-diethoxymethyl-2-phenylthioimidazole (18) was unstable and difficult to purify. 4-Bromoimidazole with two mol equiv. of t-butyl-lithium gives 1,4-dilithioimidazole, which is now shown to provide a general route to 4-substituted imidazoles.