CRYSTALLINE FORM II OF TILORONE AND METHOD OF OBTAINING THEREOF (VERSIONS) Russian patent published in 2014 - IPC C07C217/24 

FIELD: chemistry.

SUBSTANCE: invention relates to a novel stable crystalline polymorphic modification of form II of tilorone and to versions of a method of its obtaining. Tilorone is used as an anti-viral and immunomodulating substance. The crystalline form II of tilorone is characterised by a powder radiograph, which has characteristic peaks at the following values of 2θ (°): 4.39 8.82 10.53 11.94 12.14 12.37 12.73 13.10 13.29 15.14 16.43 20.72 22.57 23.89 24.11 24.49 24.71 25.70 26.28 26.55 27.42 28.78 30.82 31.60 31.95 33.27 34.82. The method of obtaining the crystalline form II of tilorone includes tilorone purification by dissolution at heating in a mixture of isopropanol and a polar solvent, selected from ethanol and water, separation of non-dissolved admixtures from the tilorone solution and spontaneous cooling of the solution with formation of crystals of the crystalline form II of tilorone, which are separated from admixtures, dissolved in the solution. Tilorone purification can also be performed by dissolution of tilorone at heating in the polar solvent, selected from ethanol and water, with separation of non-dissolved admixtures from the tilorone solution and precipitation of crystals of the crystalline form II of tilorone from the solution by isopropanol, with crystals being separated from admixtures, dissolved in the solution, in conditions of slow cooling.

EFFECT: obtaining the novel stable crystalline polymorphic modification of tilorone of form II.

14 cl, 5 tbl, 4 dwg, 6 ex