METHOD OF SYNTHESIS OF PYRAZOLE DERIVATIVES OR THEIR PHARMACEUTICALLY ACCEPTABLE SALTS Russian patent published in 1994 - IPC

FIELD: organic chemistry. SUBSTANCE: derivatives of formula or where R¹ - aryl which can be substituted with one or several substituents, for example, lower alkyl, halogen, lower alkyloxy, lower alkylthio, lower alkylsulfonyl, hydroxy, lower alkylsulfonyloxy, nitro, amino, lower alkylamino, acylamino or lower alkyl (acyl)amino; or 4-pyridyl; R² - hydrogen, methyl, substituted with amino, lower alkylamino, halogen or acyloxy; acyl; carboxy or esterified carboxy; cyano; lower akylthio; lower alkylsulfinyl or tetrazolyl; R³ - aryl substituted with lower alkyl, lower alkylthio, lower alkylsulfinyl; aminohalogen, lower alkylamino, lower alkoxy, cyano, hydroxy or acyl; or 5-(methylthio)-2-thienyl; R² - carboxy esterified with carboxy or tri(halide)methyl; R¹ - aryl substituted with one or more substituents, for example, lower alkylthio, lower alkylsulfinyl, lower alkylsulfonyl, hydroxy, lower alkylsulfonyloxy, nitro, amino, lower alkylamino, acylamino or lower alkyl(acyl)amino; or 4-pyridyl; R³ - aryl substituted with lower alkylthio, lower sulfinyl, amino, lower alkylamino, acylamino, lower alkyl(acyl)amino, hydroxy or acyl; 5-(methylsulfonyl)-2-thienyl; or 5-(methylthio)-2-thienyl; or their pharmaceutically acceptable salts. Reagent 1: diketone of formula R³COCH₂COR². Reagent 2: hydrazine of formula R¹NHNH₂ or its salt. Reaction condition: isolation in the free form or in the form of pharmaceutically acceptable salt. Synthesized compounds are used in medicine. EFFECT: improved method of synthesis of compounds indicated above.