| 摘要 |
A process for the preparation of canrenone of the formula <IMAGE> starts from an acetal of 3 beta ,17 alpha -dihydroxy-17 alpha -pregn-5-ene-21-carbaldehyde and comprises the following sequence: a) bromination in position 5,6 b) oxidation of the 3 beta -hydroxy group to the 3-oxo group with formation of the 4-ene structure c) dehydrobromination in position 5,6 with formation of the 4,6-diene structure d) ring closure in position 17 by means of a compound of six-valent chromium, e.g. chromic acid, in acid solution or else starts from dehydroepiandrosterone and entails reaction with a chloropropionaldehyde acetal in the presence of lithium to give the abovementioned starting acetal and further processing as in stages a) to d). The further processing of the canrenone prepared in this way to give derivatives thereof is also described, namely on the one hand by addition of a thiocarboxylic acid, e.g. thioacetic acid, onto the 5,6-double bond of canrenone to give corresponding spironolactones, and on the other hand by cleavage of the spiro lactone ring using metal hydroxides with formation of the metal salt of the corresponding 17 beta -carboxyethyl-17 alpha -hydroxysteroid. The products of the process are known aldosterone antagonists. The described processes provide better yields and are simpler than known methods. |
