Imidazole, structure

Chemical Name 1-[(2-chlorophenyl)diphenylmethyl]-1 H-imidazole Common Name 1-(o-chlorotrityl)imidazole Structural Formula ci... 

PS-BEMP). The reaction gave 4,5-disubsituted isothiazole in 58% yield. What was interesting was that an additional washing of the immobilized base with an electrophile (in a typical setup, 2,4 -dibromoacetophenone) gave the corresponding 1,4,5-trisubstimted imidazole in 38% yield and >95% purity. Additional efforts were done to produce only the imidazole structure by using the premixed electrophile and ethyl isothiocyanate, however, without success. 

Nishimura et that 169 may have the isomeric hydroxymethyl IH-imidazole structure. 

Their antibacterial and mutagenic activity is closely related to the reduction of the 5-nitro group, which is common to all nitroimidazole drugs, and the subsequent formation of reactive metabolites that bind to bacterial DNA, inhibiting DNA and protein synthesis in the microorganisms. Metabolism of 5-nitroimidaz-oles in mammals usually leads to covalently bound residues with a persistent imidazole structure. 

Chemical Name l-[(2-Chlorophenyl)diphenylmethyl]-lH-imidazole Common Name l-(o-Chlorotrityl)imidazole Structural Formula ... 

The classical imidazole structure (53) is not consistent with the aromatic behavior, tautomerism, and high dipole moment of the... 

H. Stark and co-workers prepared novel histamine Hs-receptor antagonists with carbonyl-substituted 4-[(3-phenoxy)propyl]-1/-/-imidazole structures. The Meyer-Schuster rearrangement was used for the synthesis of one of the compounds. The p-hydroxybenzaldehyde derivative was reacted with ethynylmagnesium bromide to afford a secondary propargylic alcohol. Upon hydrolysis with 2N HCI in a refluxing ethanol/acetone mixture, the corresponding p-hydroxy cinnamaldehyde was obtained. 

Stark, H., Sadek, B., Krause, M., Huels, A., Ligneau, X., Ganellin, C. R., Arrang, J.-M., Schwartz, J.-C., Schunack, W. Novel Histamine H3-Receptor Antagonists with Carbonyl-Substituted 4-(3-(Phenoxy)propyl)-1H-imidazole Structures like Ciproxifan and Related Compounds. J. Med. Chem. 2000, 43, 3987-3994. 

Several imidazoles have been found to inhibit NOS, including 1-phenylimidazole, 2-phenylimidazole, and 4-phenylimidazole. These imidazoles bind heme in NOS and other enzymes. A search for isoform-specific inhibitors based on an imidazole structure has led to the discovery of l-(trifluoromethylphenyl) imidazole, N-(4-nitrophenacyl) imidazole, and N-(4-nitrophenyIacyl)-2-methyI-imidazole, below (54). The nitrophenylacylimidazoles are selective for nNOS rather than eNOS inhibition. They appear to bind to the tetrahydro-biopterin site and are competitive inhibitors of tetrahydrobiopterin binding. They are noncompetitive inhibitors of arginine binding. It appears that electron-withdrawing N-1 substituents enhance activity and nNOS selectivity. 

Comparison of the structures of histamine with cimetidine and ranitidine. The latter two are H2-receptor antagonists and act on the gastric parietal cells to inhibit gastric acid production. Ranitidine, which has a furan rather than an imidazole structure, is a more potent competitive inhibitor than cimetidine. 

A survey of the applications of theoretical methods to azoles appeared in the Handbook of Heterocyclic Chemistry aromatic character, tautomerism, acidity and basicity, and general reactivity. 

Generally speaking, catalytic activity should correlate with electron density at the azole nitrogen of the imidazole structure. In addition, the basicity of a given imidazole may determine its corrosivity towards aluminum and, hence, its microelectronic compatibility. 

Similarly, several medicines or potential medicines have been made that contain imidazole. Structurally, the molecules can be vastly different and can affect very imique disease states. For example, metronidazole is an antibiotic effective against anaerobic bacteria, and it also acts as an anti-parasitic agent. It is a relatively simple functionalized imidazole. Cipralisant is a potent H3 receptor antagonist H3 antagonists are believed to have potential therapy to aid in sleep, cognition, food intake, and memory. ... 

CYP oxidation, the imidazole structure may not be the only the structural moiety creating all of the inhibition. However, imidazoles can chelate to the heme Fe of the CYP450 enzyme complex and display slow dissociative kinetics. While reversible, this can disrupt the oxidation of another drug and greatly diminish the therapeutic window that was observed in animal studies. 

Over the past decade Zeneca (Avecia) has produced two reagents designed to recover zinc selectively from iron. The first of these, ZNX-50, was based on an imidazole structure and was proposed for the extraction and separation of zinc from iron in chloride media. The second, DS5869, is a dithiodialkylphosphoramide, and although it will separate zinc from iron in sulfate liquor it will also strongly extract cadmium, mercury, bismuth, and other soft metals and also irreversibly loads copper. These are obvious disadvantages for commercial application. 

Phosphoric acid, as well as other protic electrolytes with a sufficient acidity, can be adsorbed by PBI-type polymers, because of their basic imidazole structural units. The resulting PBI-protic electrolyte systems exhibit proton cOTiductivities of about one order of... 

Active imidazoles are present throughout the course of curing, and overall curing rates (formation of polyethers) vary with imidazole structure, even though all imidazoles form adducts rapidly. Riccardi et al. [ 102] explain this discrepancy as the instability of adducts of imidazoles with epoxides. Parallel to the polymerization, there occur cleavage of N—C bonds and the deprotonation of the carbon at the 2-position of imidazole, and thus the imidazoles are regenerated. 

There are a number of advantageous attributes associated with imidazole, such as its miscibility in water and ILs, for example, imidazolium-based ILs [112— 114]. Moreover, the imidazole structure, consisting of a five-membered heterocyclic ring with two N atoms, is amenable to selective coordinate to soft metal catitms, such... 

The nitrogen atom on the bottom of the structure is bonded to a hydrogen atom and resembles the nitrogen atom of pyrrole. Three O bonds are shown. Each has one valence electron contributed from the nitrogen atom. Thus, the remaining two valence electrons of nitrogen are located in a 2p orbital. These two electrons, along with the four electrons of the two 7i bonds shown in the imidazole structure, account for six electrons of an aromatic system. 

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