STABLE CRYSTALLINE FORM OF TIPIRACIL HYDROCHLORIDE AND METHOD FOR ITS CRYSTALLIZATION Russian patent published in 2018 - IPC C07D403/06 A61K31/506 A61P35/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a novel crystalline modification III of 5-chloro-6-(2-iminopyrrolidin-1-yl)methyl-2,4(1H,3H)pyrimidinedione hydrochloride. Compound has the properties of an inhibitor of thymidine phosphorylase and enhances the antitumor effect of trifluridine. Crystalline form III has powder X-ray diffraction peaks at angles of 10.5°, 19.6°, 23.7°, 26.2° and 31.2° (at 2θ ± 0.2°), and has a purity of 90 % by mass or more. In this case, the crystal exhibits an endothermic peak, which is determined by the method of thermogravimetry and differential thermal analysis, at a temperature of about 245 °C. According to the analysis of single crystals, crystalline form III has the following crystal indicators: monoclinic system, space group P2_l, lattice constant: a = 10.3221 (14) Å, b = 9.8634 (13) Å, c = 11.6643 (16) Å, α = 90°, β = 100.317°, γ = 90°, volume of the lattice unit cell: 1169.5 (3) ų.

EFFECT: crystalline form has high stability, even at 40 °C for 6 hours.

3 cl, 3 dwg, 3 tbl, 7 ex