2.4- Dimethyl-imidazo

When compound 241 is refluxed with hydrazine hydrate, 2,6-dimethyl-imidazo[2,l- ][l,3,4]thiadiazole-5-carbohy-drazide 242 was isolated. This product, after reaction with the appropriate aldehydes, yields the corresponding... 

IQ 2-amino-3-methyl imidazo[4,5-/ quinoline nh2 r CH3 MelQx 2-amino-3,8-dimethyl imidazo [4,5-/ quinoxaline nh2 MelQ 2-amino-3,4-dimethyl imidazolOS quinoline nh2 W XH3... 

From grilled sun-dried sardines, two mutagenic fractions were obtained with high performance liquid chromatography using pBondapak Cie. Their structures were determined, by 270 MHz 1H-NMR and low- and high-resolution mass spectra, to be 2-amino-3-methylimidazo[4,5-/]quinoline (IQ) and 2-amino-3,4-dimethyl-imidazo[4,5-/]quinoline (MelQ) (12,13,14). The structures of these new compounds were confirmed by chemical synthesis. 

Reaction of imidazo[4,5-fc]pyridine (97), but not its 5-amino derivative, with perphthalic acid (49JA1885) or hydrogen peroxide in acetic acid (66UC403) gave the A( -oxide (98). Peracetic acid was used to prepare the A7 -oxides of 6-bromo-, 6-chloro, 6-bromo-5- and -7-methyl-, and 5,7-dimethyl-imidazo[4,5-fc]pyridine (98) (59JOC1455). The N-oxides can be catalytically reduced to (97) (80JHC17S7). 

Radical alkylation of 1-methyl-, 3-methyl- and 2,3-dimethyl-imidazo[4,5-c]pyridine (147) takes place at C-4 giving (148) with some dimethylation of monomethyl compounds occurring, the second methylation being at C-2 (77KGS933, 78MI41006). 

Muggli R, Tsdiopp TB, Mittelholzer E, Baumgartner HR 7-Bromo-l,5-dihydro-3,6-dimethyl-imidazo[2,l-b]quin olin-2(3H)- one(Ro 15-2041), apotent antithrombotic agent that sdectivdy inhibits platelet cyclic AMP-fdiospho esterase. J Pharmacol Exp Ther 1985 235 212-219. 

Scheme 18. Polybenzimidazole synthesis, exemplified by the polycondensation of 2,6-dimethyl-imidazo[4,5-/lbenamidazole with terephthalaldehyde...

Ryu, D.-Y. et al., In vivo mutagenicity and hepatocarcinogenicity of 2-amino-3,8-dimethyl-imidazo[4,5-/]quinoxaline (MelQx) in bitransgenic c-myc/A,lacZ mice, Cancer Res., 59, 2587, 1999. 

Amino-3,5 -dimethy l-imidazo[4,5 -/ ] quinoline (MelQ) 2-Amino-3,8-dimethyl-imidazo[4,5 /]quinoline (MelQx)... 

Imidazo[l, 2-n]imidazole, 1,6-dimethyl-MO calculations, 6, 979 Imidazo[ 1,2-n]imida2ole, 1,6-dimethyl-5-nitro-MO calculations, 6, 979... 

Imidazolidine, 4,5-dichloro-l,3-diacetyl-imidazo[4,5-6]pyrazine synthesis from, 5, 646 Imidazolidine, 1,3-dimethyl-conformation, 5, 355 Imidazolidine, diphenyl-dehydrogenation, 5, 427 Imidazolidine, 2-imino-1-substituted nitration, 5, 427... 

Imidazo[4,5-6]pyridine, 1,2-dimethyl-methylation, 5, 618 Imidazo[4,5-6]pyridine, 2,3-diphenyl-synthesis, 5, 636 Imidazo[4,5-6]pyridine, 6-halo-alkylation, 5, 616 aminomethylation, 5, 616 Imidazo[4,5-6]pyridine, 2-(4-hydroxy-6-methylpyrimidin-2-ylamino)-synthesis, 5, 637... 

Imidazo[4,5-c]pyridine, 2,3-dimethyl-radical alkylation, 5, 621 Imidazo[4,5-c]pyridine, 2-ethoxy-synthesis, 5, 635... 

Dimethyl-6-methylamino-5-quinoxalinamine (175) (prepared freshly as an ethanolic solution by catalytic hydrogenation of the corresponding nitro compound) and cyanogen bromide gave 3,4,8-trimethyl-3//-imidazo-[4,5-/]quinoxalin-2-amine (176) (20°C, 3.5 h 75%) the analogous... 

Imidazo[l,2-a]pyridines are formed by condensation of iV-arylacetylimidazoles with dimethyl acetylenedicarboxylate, [ 154H156]... 

Dioxane solutions of 4(5)-aminoimidazole (64) have been treated with several reagents [92JCS(P1)2789], Imidazo[l,5-a]-l,3,5-triazines (65 R = Ph, Me SMe) were obtained by reaction with methyl N-cyanobenzimidate (57 R = Ph), ethyl N-cyanoacetimidate (58 R = Me), and dimethyl yV-cyanodithioiminocarbonate (59 R = SMe). The uncy-clized product (68 R = H) (73%), obtained by condensation with ethyl N-cyanoformimidate (58 R = H), underwent facile cyclization to give the imidazo[l,5-a]-l,3,5-triazine (65 R = H). Likewise, the condensation adduct (69 R = H) (78%) was obtained using ethoxy methyleneurethane (60 R = H) and this underwent base-catalyzed cyclization to give the imidazo[ 1,5-a]-1,3,5-triazinone (67). Imidazo[l, 5-a]pyrimidines (66 R = H, Me) were obtained from the condensation of 4(5)-aminoimidazole... 

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