mesterolone cipionate mesterolone cipionate mesterolone cipionate is a synthetic anabolic–androgenic steroid and an androgen ester – specifically, the c17β cypionate ester of mesterolone – which was never marketed. it is administered via intramuscular injection once every two weeks and acts as a long-acting prodrug of mesterolone. the drug was studied in the treatment of depression in men along with mesterolone in the mid-1970s but was never introduced for medical use. mesterolone cipionateclinical dataother namesmesterolone cypionate; mesterolone cyclopentylpropionate; mesterolone cyclopentanepropionateroutes ofadministrationintramuscular injectiondrug classandrogen; anabolic steroid; androgen esteridentifiers iupac name phenanthren-17-yl] 3-cyclopentylpropanoate chemical and physical dataformulac29h44o3molar mass440.668 g·mol−13d model (jsmol)interactive image smiles 12cc(oc(=o)ccc3cccc3)1(c)cc1()2()cc2(c)cc(=o)c(c)12c inchi inchi=1s/c29h44o3/c1-19-17-21(30)18-27(2)15-13-22-23-10-11-25(28(23,3)16-14-24(22)29(19,27)4)32-26(31)12-9-20-7-5-6-8-20/h20,22-24h,5-18h2,1-4h3/t22-,23-,24-,27-,28-,29+/m0/s1key:twdizpbgclxsns-paxvtgjlsa-n