| abstract |
FIELD: crystal growth and pharmaceutical means. SUBSTANCE: invention relates to a new method of crystallizing organic compounds, more specifically to crystallizing steroidents, namely, estrane, endrostane, pregnane, 19-norpregnane, cholestane, and their 3- and 7-substituted esters. Invention focuses on a method of crystallization of microcrystals of pharmaceutically-active substances that enables, with no recourse to mechanical operation, preparing predetermined granulometrically homogeneous class. Method consists in that, substance is dissolved in ternary mixture formed by lipophilic solvent, hydrophilic solvent, and surfactant at temperature close to boiling temperature. Then mixture is allowed to spontaneously cool to temperature at which crystallization is initiated, after which crystals are separated. EFFECT: improved quality of crystals. 25 cl, 22 dwg, 3 tbl, 37 ex |