C-6 all having an ester sidechain at C-17 (benzoate ester bearing a Cl, F and a Br atom at C-4 position of the phenyl ring) on the 5alpha-reductase enzyme activity present in human prostate. In addition, it was also of interest to investigate the pharmacological effect on hamster flank organs diameter size. In order to study the structure-activity relationships of steroids 12a-12d, 14a-14d and 15