Nitration of 1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one derivatives

A new route for the synthesis of substituted 5-amino-4-cyanoimidazol-2-ones – precursors for the preparation of 3,6,7,9-tetrahydro-8H-purin-8-ones derivatives

“…Thus, in aqueous alkali compounds 3c-e were alkylated with dimethyl sulfate to form 1-alkyl(aryl)-3-methylimidazol-2-ones 4c-e. The regioselective alkylation of imidazolones is confirmed by a number of literature analogs [13][14][15] and also by 1 H NMR spectral data: the signals of the protons of the NMe group are found in the 3.03-3.23 ppm region. The thioamides 5c-f were formed by the reactions of compounds 3c-f with hydrogen sulfide.…”

Cyclization of substituted 2,3-diaminopyridines into derivatives of 1H-1,2,3-triazolo[4,5-b]pyridine 2-oxide in the course of nitration

“…Evidently, as shown in [3], a series of successive transformations occurring with the structure of 2,3-diaminopyridines IIа-IIc in the nitrating mixture at 0°С leads initially to the fragment of 1,2,3-triazole 2-oxide А. [4] activates the compound, and at the increasing temperature of the nitrating mixture to 70°С the nitration occurs into the position 5 of the pyridine ring.…”

6-Bromo-3-methyl-1H-imidazo[4,5-b]pyridin-2(3H)-one

“…For the synthesis of the title compound, see: Grivas & Lindströ m (1995); Smolyar et al (2007). Triclinic, P1 a = 4.4151 (1) Å b = 9.6004 (2) Å c = 10.5330 (3) Å = 116.248 (1) = 93.074 (2) = 91.687 (1) V = 399.14 (2) Å 3 Z = 2 Mo K radiation = 5.10 mm À1 T = 293 K 0.36 Â 0.17 Â 0.10 mm…”