GB777693A - Cyclopentanopolyhydrophenanthrene compounds - Google Patents

Abstract

The invention comprises compounds having the formula: <FORM:0777693/IV(b)/1> in which the 3-position is occupied by a bivalent group convertible to a keto group by acid hydrolysis, e.g. a cyclic ketal group, or a pair of univalent groups together convertible to a keto group by acid hydrolysis, e.g. a non-cyclic ketal group, compounds having the formula: <FORM:0777693/IV(b)/2> in which the 3-position is occupied by a univalent group convertible to keto by acid hydrolysis, e.g. an enol ether group, also dl-D 4-3,20 - diketo - 11 - hydroxy - pregnene and D 4-3,20 - diketo - 11 - hydroxy - isopregnene, and the process which comprises treating a 1-[2-(hydrocarbon - sulphonoxy) - ethyl] - 2 - acetonyl-polyhydrophenanthrene compound with an alkaline material, e.g. triethylamine, alkali metals, alkoxides and hydrides of alkali metals and alkoxides of alkaline-earth metals (inter alia, sodium, potassium, sodium methoxide, potassium t-butoxide, sodium isopropoxide, or sodium hydride) to produce a compound having at ring D the formula: <FORM:0777693/IV(b)/3> The reaction may be effected in a lower alkanol, benzene, toluene or ether. In effecting the ring closure the isopregnene compound is first formed and may be epimerized by treatment with alkali to the normal pregnene compounds. Compounds blocked in 3-position may be hydrolysed with acid, e.g. p-toluenesulphonic acid, perchloric acid and hydrochloric acid. The 11-hydroxy compounds may be oxidized to the corresponding 11-keto compound, e.g. by treatment with chromium trioxide/pyridine complex. Examples describe the preparation of D 4-3-ethylenedioxy - 11,20 - diketo - 17 - isopregnene and the corresponding 17-pregnene, D 4 - 3,11, 20 - triketo - 17 - isopregnene and the corresponding pregnene, D 5 - 3 - ethylenedioxy - 11-hydroxy - 20 - keto - pregnene and the corresponding 17 - isopregnene and D 4 - 3,20 - diketo - 11 - hydroxy - pregnene and the corresponding isopregnene. Specifications 733,808, 763,208, 777,691 and 777,692 also are referred to.