GB792411A - Polyhydrophenanthrene compounds - Google Patents

Abstract

The invention comprises compounds of the formula <FORM:0792411/IV (b)/1> in which the 7-position is occupied by either a divalent 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:0792411/IV (b)/2> in which the 7-position is occupied by a univalent group convertible to keto by acid hydrolysis and the compound of the formula <FORM:0792411/IV (b)/3> Compounds of the first and second formula are obtained according to one method by the oxidation with ozone of a 1-acetaldehydo-2-methallyl - 2,4b - dimethyl - 4 - keto - 1,2,3,4,4a,4b,5,-6,7,8,10,10a - dodecahydrophenanthrene appropriately substituted in the 7-position. The second method involves the oxidation with periodic acid of a 1-acetaldehydo - 2 - (b ,g - dihydroxyisobutyl) - 2,4b - dimethyl - 4 - keto - 1,2,3,4,4a,4b,5,6,7,8,10,10a - dodecahydrophenanthrene appropriately substituted in the 7-position. The compound of the third formula is obtained by acid hydrolysis of the compounds of the first and second formul . In the first method it is preferred to effect the oxidation with ozone in a lower alkanol at about - 80 DEG C., then to raise the temperature to 0 DEG C. and effect decomposition of the ozonide under reductive conditions, e.g. with zinc and aqueous acetic acid. The product may be chromatographed. In an example 2,4b-dimethyl-7-ethylenedioxy-2(b ,g - dihydroxy - isobutyl) - 1 - acetaldehydo - 4 - keto - 1,2,3,4,4a,4b,5,6,7,8,10,10a - dodecahydrophenanthrene in tetrahydrofuran and pyridine is oxidized with aqueous periodic acid to 2,4b - dimethyl - 7 - ethylenedioxy - 2 - (b - ketopropyl) - 1 - acetaldehydo - 4 - keto - 1,2,3,4,4a,4b,5,6,7,8,10,10a - dodecahydrophenanthrene. Specifications 763,208, 792,412 and 792,413 are referred to.