METHOD OF SYNTHESIS OF STEROID ESTERS Russian patent published in 1997 - IPC

FIELD: biotechnology, medicine, agriculture, veterinary science. SUBSTANCE: method involves interaction of steroid alcohols with anhydride or chloroanhydride of the corresponding acid in the presence of catalyst in medium of dialkylketone. Process is carried out at ratio of the solvent volume to steroid mass = (2.5-5.0):1. Catalyst: tertiary amine, for example, triethylamine, or 2,4,6-tris-(dimethylaminomethyl)-phenol, or 4-(dimethylamino)-pyridine or their combination taken at mole ratio = (0.0125-1.5): 1 to steroid. The end product is isolated by reaction mass dilution with two-fold mixture of water and aliphatic alcohol followed by filtration. Additional amount of the end product is obtained from mother liquor by sorption on exchange-resin and elution with organic solvent or acetic acid ester and acylation with the above indicated way. EFFECT: simplified method, improved quality and ecology safety. 3 cl