METHOD FOR PRODUCTION OF POLYMORPHOUS FORM OF 4-(3-ETHOXY-4-HYDROXYBENZYL)-N-(2,4-DIFLUORPHENYL)-5-OXO-5,6-DIHYDRO-4H-1,3,4-THIADIZINE-2-CARBOXAMIDE Russian patent published in 2022 - IPC C07D285/16 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for the production of a polymorph of 4-(3-ethoxy-4-hydroxybenzyl)-N-(2,4-difluorphenyl)-5-oxo-5,6-dihydro-4H-1,3,4-thiadizine-2-carboxamide. The method is carried out by obtainment of a solution of a compound in tetrahydrofuran with a compound concentration of 1.1-1.3 g/ml at 60°C during mixing, then, the resulting solution is filtered through a filter heated to the same temperature to a receiver heated to the same temperature to obtain filtrate, and the resulting filtrate is cooled to 4°C to obtain crystals. Resulting crystals have primitive cubic syngony, characteristics peaks of high intensity are present in powder X-ray diagram, at angles 2θ equal to 14.9°±0.1°, 16.0°±0.1°, and 27.5°±0.1°, as well as characteristic peaks of medium intensity at angles 2θ equal to 18.3°±0.1° and 26.2°±0.1°. A melting point determined by differential scanning calorimetry is in the range from 99.7 to 101.8°C.

EFFECT: obtainment of a polymorph of 4-(3-ethoxy-4-hydroxybenzyl)-N-(2,4-difluorphenyl)-5-oxo-5,6-dihydro-4H-1,3,4-thiadizine-2-carboxamide with better characteristics, such as indicators of solubility, melting point, thermal stability.

1 cl, 6 dwg, 4 tbl, 2 ex