FIELD: organic chemistry and technology. SUBSTANCE: invention relates to the synthesis of lezopitron of the formula (I) by condensation of 2-(1-piperazinyl)-pyrimidine, 4-chloropyrazole and hydrocarbon derivative of the formula (III): X(CH2)4Y, where X and Y are similar or different and mean the group to be split off: iodine, bromine, chlorine, mesylhydroxy- and tosylhydroxy-group. Process is carried out at heating, preferably at 80-180 C, under pressure 1-5 atm in medium of aprotonic polar solvent in the presence of mineral or organic base, preferably alkaline metal carbonate. Dimethylformamide, dimethylsulfoxide, isopropanol, tert.-butanol, toluene and xylene can be used as a solvent. Reaction time is 1-24 h. Condensation is carried out preferably in the presence of one or some agents of phase transfer, for example, tetrabutyl ammonium salt. EFFECT: simplified method, improved purity and high yield of the end product. 7 cl
