GB792413A - Polyhydrophenanthrene compounds - Google Patents

Abstract

The invention comprises compounds of the formula <FORM:0792413/IV (b)/1> in which the 7-position is occupied either by a bivalent group convertible to keto by acid hydrolysis or by a pair of univalent groups together convertible to a single keto group by acid hydrolysis, compounds of the formula <FORM:0792413/IV (b)/2> in which the 7-position is occupied by a univalent group which is convertible to keto by acid hydrolysis and a compound of the formula <FORM:0792413/IV (b)/3> Compounds of the first and second formul are obtained by oxidation of a 2,4b-dimethyl-2-methallyl - 1(b - hydroxyethyl) - 1,2,3,4,4a,4b,5,-6,7,8,10,10a - dodecahydrophenanthrene having a hydroxy or keto group in the 4-position and appropriately substituted in the 7-position. The oxidation can be effected with a complex of chromium trioxide and an organic base, e.g. pyridine. The compound of the third formula above is obtained by acid hydrolysis, e.g. with perchloric acid, of the compounds of the first two formul . In the 7-position the substituents may be those referred to in Specification 792,410. In an example, 2,4b-dimethyl-7-ethylenedioxy - 2 - methallyl - 1 - (b - hydroxyethyl) - 4 - hydroxy - 1,2,3,4,4a,4b,5,6,7,8,10,10a-dodecahydrophenanthrene is treated with a complex of chromium trioxide and pyridine and from the reaction product there are separated by chromatography 2,4b-dimethyl-7 - ethylenedioxy - 2 - methallyl - 1 - acetaldehydo - 4 - keto - 1,2,3,4,4a,4b,5,6,7,8,10,-10a-dodecahydrophenanthrene (main product) and the corresponding 1-(b -hydroxyethyl) and 1-(carboxymethyl)-compounds. These two latter compounds on reduction with lithium aluminium hydride give the C-11 epimer of the starting material which can be re-used. Specifications 733,808, 763,208, 777,682, 777,683, 792,411 and 792,412 also are referred to.