METHOD FOR OBTAINING OF N-ARYL-SUBSTITUTED 3H-IMIDAZO[4,5-b] PYRIDINES Russian patent published in 2018 - IPC C07D471/04 

FIELD: pharmacology.

SUBSTANCE: invention relates to a method of obtaining N-aryl-substituted 3H-imidazo[4,5-b] pyridines, formula shown below, where R=H, OCH₃, CH₃, Cl, involving nucleophilic substitution of the chlorine atom in 2-chloro-3-nitro-6-R-pyridine in a reaction with imidazole, deoxidizing isomerization recycling of N-(3-nitro-6-R-pyrid-2-yl) benzimidazoles. Nucleophilic substitution is carried out in DMF in the presence of K₂CO₃ for 1 hour at a temperature of 50°C and molar ratio of 2-chloro-3-nitro-6-R-pyridine:benzimidazole:K₂CO₃=1:1:1.5, deoxidizing isomerization recycling of N-(3-nitro-6-R-pyrid-2-yl)benzimidazoles is performed by SnCl₂⋅2H₂O at a temperature of 80°C for 20 h in a mixture of isopropanol and 18% hydrochloric acid taken in a volumetric ratio of 1:1, and molar ratio of 1-(3-nitro-6-R-pyridine-2-yl)-1H-benzimidazole : SnCl₂⋅2H₂O=1:3.5.

EFFECT: method is developed for preparation of these derivatives, which can be used as precursors for drugs.

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