α- OR β-CRYSTALLINE MODIFICATIONS OF 5'-DESOXY-N4-CARBOPENTYLOXY-5-FLUOROCYTIDINE, PREPARATION METHOD THEREOF AND PHARMACEUTICAL COMPOSITIONS BASED ON SAID COMPOUNDS

FIELD: chemistry. SUBSTANCE: disclosed are α- and β-crystalline forms of 5'-desoxy-N 4 -carbopentyloxy-5-fluorocytidine of formula (III) , their preparation method through crystallisation of the raw product from a suitable solvent and pharmaceutical compositions based on the said compounds, having anti-cancer activity. The solvent used when preparing the α-modification is an ester or a mixture of ester-containing solvents. The solvent used when preparing the β-modification is a mixture of water and alkanol or a mixture of tetrahydrofuran and diethyl ether or carbon tetrachloride. EFFECT: obtaining compounds and pharmaceutical compositions based on the said compounds, having anticancer activity. 10 cl, 2 dwg, 7 ex