Imidazole nitration

CD-bonded stationary phases are suitable for the separation of positional, geometric and optical isomers, derivatives of dansyl racemic amino acids, analogues of nicotine and nicotine analogs, arbitrates and derivatives of benzodiazepin as well as organic nitrates, imidazol derivatives, etc. Table 8.2 shows that some enantioselective stationary phases are based on modified CDs [32,33]. The first CD derivatives used as a chiral stationary phase in HPLC were hydroxypropyl, acetylated and carbamoylated /3-CD, which demonstrated better selectivity behaviors than native /3-CD. The most common commercial species of CD derivatives include water-soluble methylated CD (2,6-di-0-methyl-j8-CD) and HP-j6-CD, then acetylated CD, carboxymethylated CD, naphthyl ethyl carbamate-j8-CD,... 

Thekinetics of nitration in sulphuric acid of both pyrazole and imidazole have been studied. Data have already been quoted (tables 8.1, 8.3) to support the view that the nitration of both of these compounds at C(4)... 

Classic A/-heterocychc ligands, eg, bipyridyl (bipy), terpyridyl, imidazole, pyrazine, phenanthroline, piperazine (including alkyl- and aryl-substituted derivatives), and polypyrazol-l-yl-borates (bis, tris, and tetra), have all been found to coordinate Th(IV) chlorides, perchlorates, and nitrates. The tripodal hydrotris(pyrazolyl)borates, HBPz, have been used to stabilize organometaHic complexes (31). Bis-porphyrin Th(IV) "sandwich" complexes have been... 

Miconazole. Miconazole nitrate [22832-87-7] (Fig. 2), the 1-phenethyl-imidazole derivative first described in 1969, interferes at low doses with the cytochrome P-450 dependent ergosterol biosynthesis in yeasts and fungi. The result is accumulation of C-14 methylated sterols on the one hand and reduction of the ergosterol levels in the membranes on the other hand (12). Analogous to clotrimazole, this leads to a disturbance in the membranes it results in inhibition of ceU repHcation, mycelium development (in C. albicans) and finally, ceU death. High concentrations of miconazole, which may be achieved with topical use, disturb the orientation of phosphoHpids in the membranes, which produces leaks (13). 

Azoles can form stable compounds in which metallic and metalloid atoms are linked to nitrogen. For example, pyrazoles and imidazoles Af-substituted by B, Si, P and Hg groups are made in this way. Imidazoles with a free NH group can be Af-trimethylsilylated and Af-cyanated (with cyanogen bromide). Imidazoles of low basicity can be Af-nitrated. 

In azole chemistry the total effect of the several heteroatoms in one ring approximates the superposition of their separate effects. It is found that pyrazole, imidazole and isoxazole undergo nitration and sulfonation about as readily as nitrobenzene thiazole and isothiazole react less readily ica. equal to m-dinitrobenzene), and oxadiazoles, thiadiazoles, triazoles, etc. with great difficulty. In each case, halogenation is easier than the corresponding nitration or sulfonation. Strong electron-donor substituents help the reaction. 

Electrophilic substitution occurs readily in Af-phenyl groups, e.g. 1-phenyI-pyrazoIes, -imidazoles and -pyrazolinones are all nitrated and halogenated at the para position. The aryl group is attacked preferentially when the reactions are carried out in strongly acidic media, where the azole ring is protonated. 

The basicity of pyrazole and its relation with imidazole basicity (due both to enthalpy and entropy changes (77MI40403)) have been discussed on theoretical grounds (Section 4.04.1.2.1). The pK values of 90 pyrazoles have been determined by Gonzalez et al. (68BSF707,68BSF5009) and it is essentially his work that will be discussed below. A selection of pK values are shown in Table 28. The pK values for some other pyrazoles have been measured in connection with nitration studies (Section 4.04.2.1.4(ii)) (71JCS(B)2365). 

Imidazole, 2-amino-1 -methyl-4,5-diphenyl-tautomerism, 5, 368 Imidazole, 2-aroyl-mass spectra, 5, 360 synthesis, 5, 391, 402 UV spectra, 5, 356 Imidazole, 4-aroyl-synthesis, 5, 474 Imidazole, C-aroyl-UV spectra, 5, 356 Imidazole, aryl-nitration, 5, 396, 433 oxidation, 5, 433 Imidazole, 1-aryl-dipole moments, 5, 351 dearylation, 5, 449 ethylation, 5, 448 H NMR, 5, 353 hydroxymethylation, 5, 404 rearrangement, 5, 108 synthesis, 5, 390 thermal rearrangement, 5, 363 Imidazole, 2-aryl-chlorosulfonation, 5, 397 synthesis, 5, 475 Imidazole, 4-aryl-bromination, 5, 399 Imidazole, C-aryl-electrophilic substitution, 5, 432-433 nitration, 5, 433 Imidazole, N-aryl-reactions, 5, 448-449 structure, 5, 448-449 Imidazole, arylmercapto-... 

Imidazole, 4,5-dibromo-l-methyl-synthesis, S, 399 Imidazole, 4,5-di-t-butyl-synthesis, S, 483 X-ray diffraction, S, 350 Imidazole, 4,5-dichloro-chlorination, S, 398 synthesis, S, 398, 473 Imidazole, 4-(3,4-dichlorophenyl)-nitration, 5, 433 Imidazole, 4,5-dicyano-hydrolysis, S, 435-436 synthesis, S, 461, 472, 487 Imidazole, 4,5-dicyano-1-vinyl-synthesis, S, 387 Imidazole, 4,5-dihydro-mass spectra, 5, 360 Imidazole, 4-(dihydroxybutyl)-synthesis, S, 484 Imidazole, 4,5-diiodo-nitration, S, 396 synthesis, S, 400 Imidazole, 2,4-diiodo-5-methyl-iodination, S, 400 Imidazole, 1,2-dimethyl-anions... 

Imidazole, 1 -hydroxy-2,4,5-triphenyl-3-oxides reactions, S, 455 Imidazole, iodo-nitrodehalogenation, 5, 396-397 Imidazole, 1-iodo-reactions, S, 454 stability, S, 110 Imidazole, 2-iodo-synthesis, S, 401 Imidazole, N-iodo-, S, 393 reactions, 5, 454 Imidazole, 4-iodo-5-methyl-iodination, 5, 400 Imidazole, 2-isopropyl-4-nitro-N-nitration, 5, 351 Imidazole, 2-lithio-reactions, S, 106, 448 Imidazole, 2-mercapto-l-methyl-as antithyroid drug, 1, 171 mass spectra, 5, 358 Imidazole, 1-methoxymethyl-acylation, S, 402 Imidazole, 5-methoxy-l-methyl-reactions... 

Imidazole, 4-methyl-annular tautomerism, 5, 363 association, 5, 362 boiling point, 5, 362 bromination, 5, 398 deuteration, 5, 417 diazo coupling, 5, 403 hydrogen bonding, S, 350 hydroxymethylation, 5, 404 iodination, 5, 400 kinetics, 5, 401 mass spectra, 5, 358 melting point, 5, 362 methylation, 5, 364 sulfonation, 5, 397 synthesis, 5, 479-480, 482, 484, 489 Imidazole, 5-methyl-annular tautomerism, 5, 363 Imidazole, l-methyl-4-chloro-ethylation, 5, 386 Imidazole, l-methyl-5-chloro-ethylation, 5, 386 nitration, 5, 395... 

Imidazole, 2,4,5-trichloro-1-methyl-chlorination, 5, 398 Imidazole, 2,4,5-trideutero-iodination, 5, 401 Imidazole, 1-trifiuoroacetyl-reactions, 5, 451-452 Imidazole, 2-trifiuoromethyl-hydrolysis, 5, 432 Imidazole, 2,4,5-triiodo-nitration, 5, 396 synthesis, 5, 400 Imidazole, 1,2,4-trimethyl-photolysis, 5, 377 rearrangement, 5, 378 Imidazole, 1,2,5-trimethyl-photochemical rearrangement, 5, 377 rearrangement, 5, 378 Imidazole, 1,4,5-trimethyl-bromination, 5, 399 3-oxide... 

N,N -dimethyloxaldiamide is reacted with PCI5 to give 4-chloro-1-methyl imidazole. This is nitrated with HNO3 to give 5-nitro-1-methyl-4-chloroimidazole. Then, a mixture of 4.6 grams of anhydrous 6-mercaptopurine, 5 grams of 1-methyl-4-chloro-5-nitroimidazole and 2.5 grams of anhydrous sodium acetate in 100 ml of dry dimethyl sulfoxide was heated at 100°C for 7 hours. 

Chemical Name 1-(2-[(4-chlorophenyl)methoxy] -2-(2,4-dichlorophenyl)ethyl)-lH-imidazole nitrate... 

After this reaction-time, the evolution of hydrogen is ceased. Then there are added successively 60 parts dimethylformamide and 8 parts of p-chlorobenzylchloride and stirring and refluxing is continued for another two hours. The tetrahydrofuran is removed at atmospheric pressure. The dimethylformamide solution is poured onto water. The product, 1-[2,4-dichloro-/3-(p-chlorobenzyloxy)phenethyl] imidazole, is extracted with benzene. The extract is washed with water, dried, filtered and evaporated in vacuo. From the residual oily free base, the nitrate salt is prepared in the usual manner in 2-propanol by treatment with concentrated nitric acid, yielding, after recrystallization of the crude solid salt from a mixture of 2-propanol, methanol and diisopropylether, 1-[2,4-dichloro-/3-(p-chlorobenzyl-oxylphenethyl] imidazole nitrate MP 162°C. 

To a stirred mixture of 140 parts nitric acid (d = 1.37), 1 part sodium nitrate and 240 parts water are added portionwise 89 parts dl-1-(1-phenylethyl)-2-mercapto-5-(ethoxycarbonyl)-imidazole. After the addition is complete, the whole is stirred for 2 hours at room temperature. The free base Is liberated by addition of solid sodium carbonate and the whole is extracted with 120 parts anhydrous ether while heating. The aqueous layer is separated and extracted twice with 80 parts anhydrous ether. 

Chemical Name 1-[2,4-Dichloro- [(2,6-dichlorobenzvl)oxv] phenylethyl] imidazole nitrate Common Name —... 

Chemical Name 1 -(2,4-Dichlorophenyl)-2-( 1 H-imidazol-1 -yl)-0-(2,4-dichlorobenzyl)-ethanone oxime nitrate... 

Electrophilic bromination (and nitration) of pyrido[l, 2-a]benzimidazole (analogous to 132) cannot take place in the imidazole moiety. Initial substitution, using NBS as reagent, was shown to occur at the 8-position, and subsequently at C-4 and C-6 (90JOU1166). 

C3H4N2 288-32-4) see Bifonazole Butoconazole Clotrimazole Eprosartan Fenticonazole Isoconazole Ketoconazole Miconazole Neticonazole hydrochloride Omoconazole nitrate Oxiconazole Ozagrel 1/f-imidazole lithium salt (C,H3LiN2 55986-39-5) see Flutrimazole 2-imidazolidinone... 

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