GB943638A - New 16-oxygenated steroids - Google Patents

Abstract

The invention comprises steroids of the formula: <FORM:0943638/C2/1> in which R1 is a hydrogen atom, R2 is H(b OH,) H(b O acyl), =O, alkyl (b OH) or alkyl (b O acyl) and the alkyl group may be unsaturated, and R3 is a hydrogen atom or an acyl group, or together with R2 is a 16,17-acetal or -ketal group. They may be prepared (1) by contacting a suitable D 4-3-keto-19-nor-androstene with a fungus which causes 16b -oxygenation or an oxidizing enzyme system obtained therefrom, such a fungi of the order Moniliales, especially the genus Curvularia such as C. lunata, the order Sphaeriales such as Mycosphaerella fragariae or M. latebrosa, the order Melancholiales such as Colletotrichum phomoides or C. lindernuthianum, or the group Mycelia such as Sclerotium coffeicolum; or (2) by reducing a 3-ether of 16-epi-oestriol or a 16,17-derivative thereof with an alkali metal in liquid ammonia to give a 16b -hydroxy-19-nor-testosterone or a 16,17-derivative thereof; or (3) converting a 17-keto compound of the 19-nor-androstane into the corresponding 16-oximino compound, reducing this to a 16-keto compound and reducing this again to a 16b -hydroxy compound; or (4) enolacylating a 17-keto-steroid, treating the thus obtained D 16-17-acyloxy compound with lead tetra-acetate to form the corresponding 16b -acyloxy-17-keto-steroid and, if desired, reducing this to the 16b , 17b -dihydroxy steroid, or, if desired, converting the 17-keto compound to a 17-hydroxy-17-alkyl compound and then to the corresponding 16b -hydroxy compound by hydrolysis. Free hydroxy products may subsequently be esterified or converted into 16,17-acetals or ketals. Examples are given and a list of esterifying acids, and of aldehydes and ketones for the formation of acetals and ketals, is provided. 16-Epi-estriol 3-methyl-ether is prepared from 16-epi-oestriol and dimethyl sulphate.