testosterone formate testosterone formate testosterone formate, also known as testosterone carboxylate or testosterone methanoate, as well as androst-4-en-17β-ol-3-one 17β-formate, is a synthetic, steroidal androgen and an androgen ester – specifically, the c17β formate ester of testosterone – which was first synthesized in the 1930s and was never marketed. testosterone formateclinical dataother namestestosterone carboxylate; testosterone methanoateidentifiers iupac name phenanthren-17-yl] formate cas number3129-42-8pubchem cid151084chemspider133166comptox dashboard (epa)dtxsid80953328 chemical and physical dataformulac20h28o3molar mass316.441 g·mol−13d model (jsmol)interactive image smiles c12cc3(1cc2oc=o)ccc4=cc(=o)cc34c inchi inchi=1s/c20h28o3/c1-19-9-7-14(22)11-13(19)3-4-15-16-5-6-18(23-12-21)20(16,2)10-8-17(15)19/h11-12,15-18h,3-10h2,1-2h3/t15-,16-,17-,18-,19-,20-/m0/s1key:lmumofowzkacou-rabcqhrbsa-n