GB493996A - A process for the preparation of derivatives of oestradiol - Google Patents

Abstract

Oestradiol which is substituted in the 17-position by an acyl or carbalkoxyl group is prepared by introducing an acyl or a carbalkoxyl group into oestradiol which is already substituted at the 3-position by a benzyl or a substituted benzyl group, and thereafter removing the benzyl or substituted benzyl group by catalytic reduction. The preferred acyl radicals are aliphatic acyl radicals such as acetyl, and also the acyl radicals of di- or poly-basic acids. In the latter case acid esters are obtained the salts of which are soluble in water. In examples: (1) oestradiol-3-benzyl ether is treated with acetic anhydride for five hours on the water bath, and the acetyl-benzyl derivative treated with hydrogen in the presence of a palladium catalyst to give 17-acetyl oestradiol; (2) a benzene solution of oestradiol-3-benzyl ether is reacted with chlorocarbonic ethyl ester in the presence of pyridine and the product reduced with hydrogen in the presence of palladium to give 17-carbalkoxy-oestradiol; (3) oestradiol-3-benzyl ether is treated with succinic anhydride in the presence of pyridine for 8 hours at 100 DEG C. The benzyl group was removed as in example (2) to give oestradiol-17-succinic acid ester. Specification 428,215 is referred to.