GB499794A - Manufacture of new esters of compounds of the oestrone series - Google Patents

Abstract

Esters of the aestrone series are prepared by causing a compound of the aestrone series to react with an acylating agent of the fatty acid series having in its acid residue more than three carbon atoms. By compounds of the aestrone series there is comprised those compounds of the aestrin series containing a keto group at the 17-position of the cyclopentanopolyhydrophenanthrene nucleus. Compounds of this series mentioned are aestrone, equiline and equilenine. Suitable acylating agents are the fatty acids themselves, or their anhydrides, halides or esters formed with alcohols of low molecular weight (exchange esterification). The fatty acids may have a straight or brached chain, and may be saturated or unsaturated. Acids specially mentioned are butyric, valeric and capric acid. In examples: (1) aestrone is esterified in the presence of pyridine with n-butyric anhydride for 1 1/2 hours at 110 DEG C. The ester crystallizes on dilution with water and is purified by crystallization from hexane. In a similar manner the isobutyrate and the stearate may be obtained. Instead of n-butyric anhydride, methyl-n-butyrate may be used as the acylating agent. In the place of pyridine there may be used dimethylaniline or quinoline, or the reaction may take place in the absence of a base; (2) aestrone is esterified in the presence of dry pyridine with n-valeric chloride, and worked up as in example (1). Instead of n-valeric chloride, the corresponding bromide may be used. In a similar manner, aestrone caprate may be obtained. As acylating agents there may also be used compounds which contain the radical of crotonic, angelic, isovaleric, capronic, caprylic, or lauric acid. A sample has been furnished under Sect. 2 (5) of aestrone-n-aenanthate prepared by esterifying aestrone with aenanthyl chloride (heptyloyl chloride) at room temperature.