A new class of long-acting hormonal steroid preparation: synthesis of dimeric androgens coupled at C3-C3 and C-17-C3 and of an androgen-progestogen combination

3β-Hydroxy-4-androsten-17-one was prepared from 4-androsten-3, 17-dione according to the method of Klimstra and Colton (1) and dimerized by means of esterification with succinic acid. The reduction with lithium-tri-t-butoxyaluminium hydride gave a testosterone derivative coupled between C₃-C₃ which showed after a single Injection of 10 mg a protracted but relatively weak androgenic effect in castrated male rats. The direct esterification of testosterone hemisuccinate with 4-androsten-3β,17β-diol gave the testosterone derivative coupled between C₁₇-C₃ which showed a more even and more protracted time response curve than testosterone enanthate. The testosterone-ethynodiol succinate also coupled between C₁₇-C₃, showed an androgenic depot-effect similar to that of the dimeric C₁₇-C₃ testosterone derivative.