Imidazoles benzimidazolate

Several biologically and pharmacologically active compounds have been prepared from the condensation of the acid chloride of 1-naphthoxyacetic acid with carbazole, iadole, or pyrrole ia 2A[ NaOH solution ia ethanol (63). Also, naphthyloxy derivatives of imidazole, benzimidazole, and benzotriazoles have been synthesized and screened for their antimicrobial, analgesic, and antiinflammatory activities. 2-Naphthyloxy derivatives are comparatively more active than 1-naphthyloxy derivatives (64). 

Most of the examples listed are pentacyanide, corrinoid, or DMG complexes. The axial ligands are not identified in the tables, but are as follows corrinoids, 5,6-dimethylbenziminazole (cobalamins), H O or none (cobinamides), (DMG)2, usually pyridine or H2O, less frequently NHj, imidazole, benzimidazole, PBuj, etc. The nature of the axial and equatorial ligands may have a striking effect on reactivity, but few direct comparisons are available these are discussed in the next section. 

Other chemicals evaluated but not yet adopted commercially include organophosphorus compounds, triphenyltin compounds, quaternary ammonium salts, imidazoles, benzimidazoles, carbamates and the precocene anti-juvenile hormones [517]. Although none of the above has found use as an insect-resist agent, several have been used as antimicrobial agents for textiles. 

These methods have been applied mainly to imidazol-, benzimidazol-, thiazol-, and benzthiazol-based car-benes,255,274,275 but there are also examples with triazols and tetrazoles.274 In the following, a few representative examples are presented which illustrate the strategies. The complex with a carbazol ligand shows strong luminescence (Scheme 69).272... 

Het = imidazoles, benzimidazole, pyrazoles, indazole triazole, pyrrole, indole... 

Complex 2b also catalyzes the addition of imidazoles, benzimidazoles, and several purines to methyl allylic carbonates (Scheme 26) [76]. These reactions occurred with good yields and excellent enantioselectivities. -substituted heterocycles are found in a number of compounds that exhibit a range of biological activity. The syntheses of several pharmacologically active compounds were conducted with yields that were improved over those published previously. 

A similar chemistry to that described for (substituted) pyridine rhenium(V) oxo complexes is also observed for other heterocyclic nitrogen donor ligands such as pyrimidine, pyrazine, substituted imidazoles, benzimidazoles, or benzotriazole. ... 

Imidazoles/benzimidazoles and chiral carbinamines are of particular importance [73, 74], Recently, Leighton et al. developed a method for enantioselec-tive imidazole directed allylation of aldimines and ketimines [75] with an analogue of 31. 

Photolysis of azolediazonium tetrafluoroborates, by the method of Kirk and Cohen (73JA4619), is a general reaction in the pyrazole, imidazole, benzimidazole and triazole series and is of synthetic interest to obtain fluoroazoles. 

Domariska, U., Pobudkowska, A., and Rogalski, M. Solubility of imidazoles, benzimidazoles and phenylimidazoles in different organic solvent, /. Chem. Eng. Data, 49, 1082, 2004. 

A thermodynamic analysis (86UP1) of the effect of annelation on the acid-base properties of the couples imidazole/benzimidazole and pyra-zole/indazole in aqueous solution has shown that this effect is essentially determined by the enhanced electronic delocalization in the case of the anions of the benzazoles. The differential steric hindrance to solvation, on the other hand, does not seem to play a significant role. 

Due to the biological significance of some azoles (pyrrole, indole, imidazole, benzimidazole) and the consequences of acid-base equilibria in their functions, a continuous interest in the behavior in water is to be expected. To quote a significant approach, imidazole is being used to determine the intra- and extracellular acidity by H-NMR (82MI4 86UP13). 

Materials. Imidazole, benzimidazole, and glucosamine hydrochloride were obtained from the Eastman Kodak Co., and used without further purification, after drying for several days over anhydrous calcium chloride. Stock solutions of nickel nitrate and nickel chloride were analyzed by precipitation with dimethyl-glyoxime. Stock solutions of cadmium nitrate were analyzed gravimetrically by conversion to cadmium sulfate. 

The electrochemical generation of a nitrilimine provides an entrance to a wide range of heterocyclic systems via anodic oxidation of aldehyde hydra-zones. The same reaction was used for annelation of various heterocyclic systems,86 e.g., substituted pyridines, quinolines, isoquinolines, indoles, imidazoles, benzimidazoles, and benzotriazoles. 

Nitroimidazole Imidazole Benzimidazole 2-Methylbenzimidazole 2-Methyl-5-nitrobenzimidazole 2-Hydroxy benzimidazole Indole... 

Five-Membered Ring Heterocycles with Two Hetero Atoms Imidazoles, Benzimidazoles, 1H-pyrazoles, Oxazoles, Isoxazoles, Thiazoles, and Indazoles... 

The ultraviolet spectra of 2-imidazolones186 and cyanoimidazoles156 have been measured, while the spectra of aryl-substituted imidazoles, benzimidazoles and naphthimidazoles have been discussed previously.3... 

Simple imidazoles are much less soluble in nonpolar solvents. For example, 177-imidazole, 2-methyl-177-imidazole, benzimidazole, 2-methylbenzimidazole, 2-phenylimidazole, 4,5-diphenylimidazole, and 2,4,5-triphenylimidazole have very low solubility in chloroalkanes (dichloromethane, 1-chlorobutane), toluene and 2-nitrotoluene. Among them, the solubility of phenylimidazoles is significantly lower than that of 17/-imidazole or benzimidazoles in all of the solvents <2004CED1082>. 

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