摘要 |
<p>The invention comprises 17b -acyloxy-des-A-estr-9-ene-5-one derivatives of the general formula: <FORM:0930975/IV(a)/1> where R indicates =O or (a -H)OH and Ac represents an acyl radical derived from an organic carboxylic acid, preferably a benzoyl radical. The 5-cyclic-ketals of 17b -acyloxy-des-A-estr-9(II)-en-5-ones and of 17b -acyloxy - 9a ,11a -epoxy-des-A-estran-5-ones are also novel compounds. The 17b -acyloxy-des-A-estr-9-en-5-one derivatives are made reacting a 17b -acyloxy-des-A-estr-9-en-5-one with a ketalizing agent, e.g. ethylene glycol in the presence of p-toluene sulphonic acid, to form the 5-cyclic ketal which is reacted with an epoxidizing agent, e.g., perphthalic acid, to yield the corresponding epoxy compound, and the latter is treated with an acid reagent, e.g. a mixture of acetic acid, ethyl acetate and water, to open the epoxide bridge and hydrolyse the ketal yielding the 11-hydroxy-17b -acyloxy-des-A-estr-9-en-5-one of the above general formula where R is (a -H)OH. This product may be treated with an oxidising agent, such as manganese dioxide, to yield the 17b -acyloxy-des-A-estr-9-ene-5,11-dione having the above general formula where R is =O. Detailed examples are given in which the benzyloxy derivatives are formed and the ketal is the ethylene ketal. Other acyloxy substituents mentioned are acetoxy, trimethylacetoxy, propionyloxy, b - cyclopentylpropionyloxy phenylpropionyloxy, 4,4 - dimethylpentanoyloxy, 10-undecanonyloxy and hexahydrobenzoyloxy. The propylene ketal is also mentioned.</p> |