METHYL BENZIMIDAZOLYL

The l-(7V-methyl)benzimidazolyl-3-benzimidazolyl-2-oxapropane ligand (107) shows coordination through the N20 donor set of the ligand, a water molecule and an acetonitrile to give a five-coordinate distorted trigonal-bipyramidal metal center.123 This contrasts with the behavior of the related thiapropane ligand that forms bidentate complexes with zinc. 

Still another example is an initiating system composed of 7-diethylamino-3 -(2 -N-methyl-benzimidazolyl)-coumarin and diphenyliodonium hexafluorophosphate. This composition initiates the polymerization of methyl methacrylate in visible light. After the dye absorbs flic light energy, quick electron transfer takes place from the dye to the iodonium salt to produce free radicals. " The light induced reaction is claimed to occur mainly through the excited singlet state of the coumarin and results in low sensitive to O2. The fluorescence of the coumarin compound was reported to be quenched efficiently by the iodonium salt. " The reaction was observed to be in accord with the Stem-Volmer equation. The influence of the concentration of coumarin on the polymerization rate of methyl methacrylate led to the conclusion that the free radicals from coumarin act mainly as chain terminators. ... 

The simple methyl compounds do indeed contain methyl groups, e.g., methylthiazoles exist as such and not in the methylene form."" The structures of compounds of the pyrophthalone type containing a benzimidazole and benzthiazole nucleus, e.g. 228, have been discussed. Bis (benzimidazolyl) methanes (229) absorb light in the... 

The whole is slowly heated to 85°C and stirred at this temperature for 45 minutes. The reaction mixture is cooled and the precipitated product is filtered off. It is washed successively with water and ethanol, dried and crystallized from a mixture of acetic acid and methanol, yielding methyl N-[5(6)-benzoyl-2-benzimidazolyl] carbamate MP 288.5°C. 

Spontaneous self assembly of a dinuclear triple helical complex is observed with linked bis-[4,5]-pineno-2,2 -bipyridines. Studies by electrospray mass spectrometry, CD and NMR determined that the major species in solution was a complex of Zn L = 2 3 stoichiometry with a triple helical structure and an enantiomerically pure homochiral configuration at the metal centers. The preference for the formation of one of the possible stereoisomers over the other is of interest.265 Another binuclear triple helical complex is formed from zinc addition to bis[5-(l-methyl-2-(6-methyl-2 -pyridyl)benzimidazolyl)]methane. Spectrophotometric titrations with a zinc solution... 

A suitable model for the oxygen carrier protein hemerythrin is [Fe2(Et-HPTB)(OBz)](BF4)2 (Et-HPTB = AWAT,iV -tetrakis[(N-ethyl-2-benzimidazolyl)methyl]-2-hydroxy-l,3-diaminopropane, OBz = benzoate). It can mimic the formation of a binuclear peroxo iron complex in the natural system (101). The measured value of -12.8 cm3 mol1 for the activation volume of the oxidation reaction together with the negative value of the activation entropy confirm the highly structured nature of the transition state. 

The amino group of 5-benzimidazolyl- and 5-benzotriazolylaminomethy-lenemalonates (1471, X = CH and N) was alkylated with methyl iodide in DMF in the presence of potassium carbonate in 43-91% yields (89CCC713). 5-Benzimidazolylaminomethylenemalonate (1471, X = CH) was also alkylated on the amino group with ethyl iodide and benzyl chloride, or with methyl iodide in dimethoxyethane, or dimethyl sulfate in THF in the presence of sodium hydride. 

Singh, R.P. and Chiba, M. Solubility of benomyl in water at different pHs and its conversion to methyl 2-benzimidazolecarba-mate, 3-butyl-2,4-dioxo[l,2-a]-s-triazinobenzimidazole, and l-(2-benzimidazolyl)-3-/ -butyl urea. J. Agric. Food Chem., 33(l) 63-67, 1985. 

Benzimidazolyl)-3-methyl-chinoxalin (24% Schmp. 191-192°) entsteht als Nebenprodukt bci dcr sauren Cyclisierung von 1,2-Diamino-benzol mit 3-Hydroximino-2-oxo-butan mit Brom. Hauptprodukt ist 2-Brommethyl-3-methyl-chinoxalin (71%), das vcrmutlich mit weiterem 1,2-Diamino-benzol reagiert hat187. 

Benzimidazolyl)-hydroxy-methyl]-penicillansdure-KaUum-Salz 100%... 

HjC-I Accton N2 0-5" 1 -Butyl-3- (l-methyl-2-benzimidazolyl) -imid-azolium-iodid 76 156-158 403... 

Methyl-benzimidazol dimerisiert ebenfalls bei der Acylierung mit Benzoylchlorid und Tri-ethylamin als Base zu 3-Benzoyl-l-methyl-2-(l-methyl-2-benzimidazolyl)-2,3-dihydro-benzimid-azol (I 37% Schmp. 170-171°). Fuhrt man die Umsetzung statt bei 20° bei 140° (Ampulle) durch, so isoliert man 2-Benzoyl-1-methyl-benzimidazol (II 92% Schmp. 71 - 72°)417. Das Di-mere I laBt sich thermisch ebenfalls zu 2-Benzoyl-l-methyl-benzimidazol ( 61%) spalten. Die basische Oxidation des Dimeren I liefert dagegen fast quantitativ 1, Y-Dimethyl-2,2-bi-(benzimidazolyl) (III)417. 

Most of the older methods of fluorimetric analysis of pesticides involved hydrolysis to form fluorescent anions. Co-ral (coumaphos) [147] was hydrolyzed in alkali to the hydroxybenzopyran, which was subsequently determined by means of its fluorescence. Guthion (azinphosmethyl) was hydrolyzed to anthranilic acid for fluorimetric analysis [148,149]. A method was developed [150] for Maretin (N-hydroxynaphthalimide diethyl phosphate) in fat and meat which involved hydrolysis in 0.5 M methanolic sodium hydroxide followed by determination of the fluorescence of the liberated naphthalimide moiety. Carbaryl (1-naphthyl N-methylcarbamate) and its metabolites have been determined by a number of workers using base hydrolysis and the fluorescence of the resulting naphtholate anion [151-153]. Nanogram quantities of the naphtholate anion could be detected. Zectran (4-dimethylamino-3,5-xylyl N-methylcarbamate) has been determined by the fluorescence of its hydrolysis product [154]. The fluorescence behaviour of other carbamate insecticides in neutral and basic media has been reported [155]. Gibberellin spray used on cherries has been determined fluorimetrically after treatment with strong acid [156]. Benomyl (methyl N-[l-(butylcarbamoyl)-2-benzimidazolyl]carbamate) has been analyzed by fluorimetry after hydrolysis to 2-aminobenzimidazole [157]. 

PHENOL, p-(5-(5 (4-METHYL-1 -PIPERAZINYL)-2-BENZIMIDAZOLYL)-2-BENZIMIDAZOLYL) -, TRIHYDROCHLORIDE... 

Chemical Name Methyl-N-[5(6)-p-fluorobenzoyl-2-benzimidazolyl]carbamate Common Name -Structural Formula ... 

A mixture of 89 parts of S-methylisothiourea sulfate, 6.05 parts of methyl chloroformate in 7 parts of water is cooled, and at a temperature of 5°C to 10°C, sodium hydroxide solution 25% is added until pH equals 8. Then there are added successively 6.4 parts of acetic acid, 2.6 parts of sodium acetate and 8.9 parts of 3,4-diamino-4 -fluorobenzophenone hydrochloride and the whole is stirred while heating at 85°C for 45 minutes (during this reaction time, water and 2-propanol is added). The precipitated product is filtered off, washed with methanol and recrystallized from a mixture of 200 parts of acetic acid and 80 parts of methanol, yielding methyl N-[5(6)-p-fluorobenzoyl-2-benzimidazolyl] carbamate MP > 260°C. 

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