17α-二氢马烯雌酮

17α-Dihydroequilin, or α-dihydroequilin, also known as estra-1,3,5(10),7-tetraene-3,17α-diol, is a natural estrogen found in horses that is closely related to equilin and equilenin. The compound, as the sodium salt of its sulfate ester, is present in the pharmaceutical drug Premarin, a conjugated estrogenic extract of the urine of pregnant mares, and is the third highest quantity constituent in the formulation (13.8%).