FIELD: chemistry, pharmaceutics.
SUBSTANCE: claimed invention relates to improved method of obtaining sulphinyl compound of formula (I) 
or its pharmaceutically acceptable salt, hydrate or solvate, which includes oxidation of sulphide compound of formula (II) 
, where in both formulae (I) and (II) R1 and R3 are selected from group including hydrogen, methyl or C1-4alkoxy, R2 is selected from group including substituted or unsubstituted C1-4alkoxy, and R4 is selected from group including hydrogen or substituted or unsubstituted C1-4alkoxy; which differs in the following: oxidiser, including water solution of hypohalogenite of alkali or alkali earth metal in concentration from 2 to 5% is added into suspension or solution of sulphide compound of formula (II), obtaining reaction mixture, in which, at least, during said oxidation solution of hydroxide of alkali or alkali earth metal is present, value of reaction mixture pH, at least, during said oxidation is within the range from 9 to 12; and, optionally, sulphinyl compound of formula (I) is converted into its pharmaceutically acceptable salt, hydrate or solvate.
EFFECT: obtaining sulphinyl compounds with greater output and lower amount of admixtures.
14 cl, 4 ex
