PYRROLO[2,3-C]PYRIDINES AS IMAGING AGENTS FOR NEUROFIBRILLAR TANGLES Russian patent published in 2019 - IPC C07D471/04 A61K31/437 A61K31/4709 A61K51/04 A61P25/28 

FIELD: chemistry.

SUBSTANCE: invention relates to a compound of formula (I):

or pharmaceutically acceptable salts thereof, where: X is CH or N; R is hydrogen or -C_1-6alkyl, said alkyl is optionally substituted with 1–3 groups R^a; R¹ is hydrogen, -C_1-6alkyl, -CN, -C_2-6alkenyl, -(CH₂)_nOR or -(CH₂)_nhalogen; R² is -C_1-6alkyl, -OC_1-6 alkyl, -C_2-6alkenylR³, -C_2-6alkynylR³, pyridine, pyrazole, piperidine, pyrimidine, imidazole, triazole, thiazole, pyrazine, quinoline, naphthyl, -NC(O)C_6-10phenyl, -C (O) NC_6-10 aryl, said alkyl, alkenyl, alkynyl, pyridine, pyrazole, piperidine, pyrimidine, imidazole, triazole, thiazole, pyrazine, quinoline, naphthyl, phenyl and aryl are optionally substituted with 1–3 groups R^a; or adjacent R¹ together with R² can form phenyl, pyrrole, furan, pyridine, piperidine, formed bicyclic ring, optionally substituted with 1–3 R^a groups; R³ is hydrogen, -C_1-6alkyl, - (CH₂)_nN (R)₂, phenyl, pyridyl, thiazole, which are optionally substituted with 1 group R^a; R^a is -C_1-6alkyl, phenyl, pyridine, -CN, NO₂, (CH₂)_nhalogen, (CH₂)_nOR, - (CH₂)_nN(R)₂; R^b is hydrogen and -C_1-6alkyl,; and n equals 0–4.

EFFECT: compounds can be used for treating Alzheimer's disease and other neurodegenerative diseases characterized by tau protein pathology.

24 cl, 2 dwg, 2 tbl, 57 ex