Syntheses of various classes of fused-imidazoles are reported. The key to their successful synthesis depends on the reaction of N-vinyl-1H-imidazole with the π-deficient compounds under basic conditions. Reaction of the target imidazole with 1,1,2,2-tetracyanoethylene and dimethyl acetylenedicarboxylate afforded pyrrolo[1,2-a]imidazoles. On the other site, reaction of the target imidazole with ...

Human carbonic anhydrases (CAs) are zinc metalloenzymes that catalyze the hydration and dehydration of CO2 and HCO3 (-), respectively. The reaction follows a ping-pong mechanism, in which the rate-limiting step is the transfer of a proton from the zinc-bound solvent (OH(-)/H2O) in/out of the active site via His64, which is widely believed to be the proton-shuttling residue. The decreased cataly...

A one pot four-component reaction of 9,10-phenanthraquinone, aromatic aldehyde, aniline, and ammonium acetate was designed for the preparation of tetrasubstituted imidazoles (phenanthro[9,10-d]imidazole) derivatives in the presence of SBA-Pr-SO3H as a mesoporous solid acid catalyst. Phenanthro[9,10-d]imidazole derivatives were produced by the use of this technique in short reaction times and go...

molecular modeling analysis of charge density and heat of fornation by pm3 method as well as c, h nmr and 2d-nmr measurements of histidine (substrate) and some of its derivatives as histidine decarboxylase inhibitors were performed. it was established that the atom, usually nitrogen, which forms internal aldimine with pyridoxal5 -phosphate (plp), (coenzyme), has negative and almost equal charge...

Imidazole and phenyl rings are fused at positions 4 5 to form the benzimidazole structure. The mono- disubstituted derivatives extremely intriguing heterocyclic chemical compounds. They can be synthesized using a straightforward condensation method between o-phenylenediamine carbonyl compound under various conditions as well nucleophilic substitution reaction. catalytical effects of derivatives...

Leishmaniasis is a neglected tropical disease (NTDs), endemic in 88 countries, affecting more than 12 million people. The treatment consists in pentavalent antimony compounds, amphotericin B, pentamidine and miltefosine, among others. However, these current drugs are limited due to their toxicity, development of biological resistance, length of treatment and high cost. Thus, it is important to ...

It has been documented that 5-methylene-Meldrum's acid derivatives (1, 12 ) and their enols (2, 13) can undergo fragmentation to malonic anhydrides (4, 19 ), carboxyketenes (3, 16) and methyleneketene (5, 21 , 35 ), as well as cyclization to pyrrole-3-one and thiophene-3-one derivatives 11a,b (but not furan-3-ones 11c ) under the conditions of flash vacuum thermolysis (FVT). Here we report theo...