The molecule is a steroid that has a structure based on a 21-carbon (pregnane) skeleton. Note that individual examples may have ring substituents at other positions and/or contain double bonds, aromatic A-rings, expanded/contracted rings etc., so the formula and mass may vary from that given for the generic structure.
17-ethyl-10,13-dimethyl-2,3,4,5,6,7,8,9,11,12,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthrene