Synthesis of benzimidazole derivatives

A general method for the synthesis of symmetrical imidatricarbocyanines is proposed. A number of dyes of this group were synthesized, and the positions of their light absorption maxima in alcohol solution were determined.See [1] for communication VIII.Translated from Khimiya Geterotsilicheskikh Soedinenii, No. 11, pp. 1562–1563, November, 1976.     

Synthesis of benzimidazole derivatives

In an aqueous medium, the reaction of N-sodio-2-methylbenzimidazole with monohalogen-substituted nitrogenous aromatic heterocycles containing the halogen in the position to the nitrogen atom may be considered as amethod for obtaining N-betaryl-2-methylbenzimidazoles. 1-(Benzoxazol-2-yl)- and 1-(benzothiazol-2-yl)-2-methylbenzimidazoles have been synthesized; imidacyanine dyes have been obtained with benzothiazol-2-yl groups on the nitrogen atoms of the benzimidazole nuclei from the methiodide of the latter.For Communication V, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1542–1544, November, 1973.     

Synthesis of benzimidazole derivatives

New bases and quaternary salts — 2-methylbenzimidazole derivatives — containing 2-pyridyl residues as a substituent in various positions of the benzimidazole ring were synthesized. Benzimidazolium salts of a new type with hetaryl groups attached to both nitrogen atoms were obtained. Imidacyanines were synthesized from the quaternary salts of pyridyl-substituted 2-methylbenzimidazoles, and the chief light-absorption maxima of these dyes were determined.See [1] for communication IVTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 687–690, May, 1972.     

Synthesis of benzimidazole derivatives

Phenylhalides of 1-phenyl-2-methylbenzimidazole were synthesized and converted to a new type of imidacyanin dye with phenyl groups on both nitrogen atoms of the benzimidazole residue. The heretofore unknown imidadicarbocyanins were obtained from quaternary salts of 1-phenyl-2-methylbenzimidazole (or its derivatives) which contain electronegative substituents in the 5 position.See [1] for Communication II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1559–1561, November, 1970.     

Synthesis of fluorine-containing benzimidazole derivatives

Various fluorine-containing benzimidazoles were obtained by the reaction of o-phenylene-diamine, 3,4-diaminotoluene, and 1,2-diamino-4-chlorobenzene with hexafluoropropene or perfluoro(methyl vinyl ether) in DMF. A new efficient method of synthesis of 2-(1,2,2,2-tet-rafluoroethyl)benzimidazole by the reaction of o-phenylenediamine with hexafluoropropene in the presence of diethylamine or dimethylamine in ethyl acetate is developed.     

Synthesis of polycyclic fused benzimidazole derivatives

Am easy method for the synthesis of tetraeyclie systems containing an imidazole and an iso-thiazole or an imidazole and a thiazine ring, by reacting 2H-1,3-benzothiazine-2-thion-4(3H)one with aromatic primary diarnines is reported. The structures were assigned based upon mass spectra and modes of cleavage of the compounds. The most important fragments are described.     

Synthesis of N-glycosides of benzimidazole and its derivatives

N-Benzimidazolylglucopyranosides were synthesized by condensation of N-trimethylsilyl derivatives of benzimidazole and its 2,5,6-trisubstituted derivatives with acetobromoglucose with subsequent removal of the protective groups. The configuration of the glycoside center was proved on the basis of PMR spectral data.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 812–814, June, 1984.     

Synthesis and tuberculostatic activity of new benzimidazole derivatives

The reactions of o-phenylenediamine and 3,4-diaminotoluene with such acids as 3-cyclohexylpropionic, 4-phenylbutyric, 4-cyclohexylbutyric, 3,3-diphenylpropionic, and 3,4-dimethoxyphenylacetic resulted in the formation of the corresponding 2-substituted benzimidazoles. These compounds were transformed into methane-and benzenesulfonamide derivatives. The benzimidazole derivatives obtained were tested in vitro for their tuberculostatic activity. Compounds with good activity (MIC 6.2-25 μg/ml) have been found. Published from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 697–700, May, 2006.     

Researches on imidazole derivatives XL. Synthesis of benzimidazole derivatives of psilocine

Reaction of 2, 3-dinitroaniscle with N, N-dimethylethylenediamine leads to replacement of the nitro group in position 2. The resultant compound is used to synthesize benzimidazaole analogs of the naturally occuring halucinogenic drug psilocine.     

Researches on imidazole derivatives XL. Synthesis of benzimidazole derivatives of psilocine

Reaction of 2, 3-dinitroaniscle with N, N-dimethylethylenediamine leads to replacement of the nitro group in position 2. The resultant compound is used to synthesize benzimidazaole analogs of the naturally occuring halucinogenic drug psilocine.     

Synthesis of fungitoxic derivatives of benzimidazole with a radioactive label

Methyl-1-butylcarbamoyl-2-benzimidazolylcarbamate with a radioactive label in the imidazole ring or methoxy group was obtained by successive reaction of barium C¹⁴-cyanamide with methyl C¹⁴-chloroformate, o-phenylenediamine, and butyl isocyanate.     

Synthesis and antioxidant properties of benzimidazole derivatives with isobornylphenol fragments

Russian Chemical Bulletin - A series of new 2-substituted-1H-benzimidazoles was synthesized on the basis of 4-hydroxybenzaldehydes. Their antioxidant properties were evaluated in the in vitro...     

新型苯并咪唑衍生物的合成及生物活性研究

以取代苯酚为原料,合成8个新型的2-苯氧甲基苯并咪唑类化合物,通过1H-NMR和HRMS确认其结构。MTT法测试其抗肿瘤活性,实验结果表明,大部分化合物具有较好的广谱抗肿瘤效果,其中化合物2h对大多数肿瘤细胞株的IC50值均达到了低微摩尔水平,对人胰腺癌(BxPC-3)的IC50达到3.6μM。试管二倍稀释法测试其抗菌活性,实验结果表明,目标化合物显示出抗菌活性,化合物2a对粪肠球菌和金黄色葡萄球菌的MIC达到16μg/mL。     

Synthesis of benzimidazole derivatives as potential H1-antihistaminic agents

Several types of benzimidazole derivatives were prepared and were screened for H ₁-antihistaminic activity. Most of the compounds showed potent antihistaminic activity in vitro. Among them 2-[(1-piperazinyl)methyl]-benzimidazoles 14 and 2-[(1-homopiperazinyi)methyl]benzimidazoles 15 exhibited potent activity also in vivo.     

Studies of benzimidazole derivatives

It was found that the formation of 2,5- and 2, 6-azobenzimidazoles, formed during the action of nitrosyl sulfuric acid on 2-amino-2-alkyl (phenyl, benzyl) benzimidazoles, occurs by azo combination of the extremely active salt of benzimidazole-2-diazonium obtained at first with the original amine. The azo compound is formed from 2-aminobenzimidazole substituted in position 5 and 6 only in the presence of 2-dimethylamino-1-methylbenzimidazole or other azo constituents. In the presence of substitutes, which hinder azo combination, 2,2-diazoaminobenzimidazoles stable also in strongly acid medium may constitute the product of the reaction.For part XIX, see [1].     

Investigations of benzimidazole derivatives

3-(1-Methyl-2-benzimidazolyl)acrylic acid was obtained by the reaction of 1,2-dimethylbenzimidazole with chloral and subsequent hydrolysis of the condensation product. The hydrochloride of the chloride of this acid and its esters and amides were synthesized. The methyl and ethyl esters of the acid were synthesized by the Wittig reaction. The IR and UV spectra of the compounds obtained are presented.See [9] for Communication XXIV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1566–1568, November, 1970.     

Investigation of benzimidazole derivatives

The hydrochlorides of the corresponding 2-benzimidazolylmethylhydroxamoyl chlorides were synthesized by the chlorination of 1-methyl-2-formylbenzimidazole oxime and its 5-methyl and 5-nitro derivatives, and 2-benzimidazolylmethylnitrolic acids were obtained by nitration of the oximes. The products of these transformations react with acetylacetone and benzoylacetone in the presence of bases to give 1,5-substituted 3-[2-benzimidazolyl]-4-acyl-5-methylisoxazoles.See [1] for communication XXVII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 812–815, June, 1972.     

Investigation of benzimidazole derivatives

A number of bis(1-benzimidazolyl)alkanes (I) were synthesized, and their behavior toward sodium amide and potassium hydroxide was studied. While compounds with n=3-5 (Ic-Ie) are aminated by NaNH₂ and hydroxylated by KOH to give diamines (II) and bisbenzimidazolones (III), Ia,b with n=1, 2 decomposed under the influence of these reagents. Considerations regarding the possible reasons for this phenomenon are stated.See [1] for communication XXVIII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1418–1421, October, 1972.     

Investigations of benzimidazole derivatives

The synthesis of 1-tert-butyl-, 1-nonyl-, and 1-undecylbenzimidazoles is described. The behavior of these compounds with respect to sodium amide and dilute alkali was studied. A number of new 2-aminobenzimidazoles and benzimidazolones were synthesized.See [1] for communication XXVI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 665–668, May, 1971.     

Investigation of benzimidazole derivatives

Under the influence of nitrosylsulfuric acid, 5- and 6-bromo-substituted 2-amino-1-methylbenzimidazoles are converted, as a result of self-coupling, to, respectively, 2,5- and 2,6-azobenzimidazoles, which are resistant to reductive cleavage. 5,6-Dibromo-2-amino-1-methylbenzimidazole forms similarly constructed azo compounds by splitting out of one of the bromine atoms. The behavior of bromo-substituted 2-aminobenzimidazoles toward nitrosylsulfuric acid in the presence of arenes was studied.See [1] for communication XXIX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1690–1695, December, 1972.