24-Methyl-lanosta-7,25-dien-3-one

THE TITLE COMPOUND [SYSTEMATIC NAME: 17-(5,6-di-methyl-hept-6-en-2-yl)-4,4,10,13,14-penta-methyl-1,5,6,10,11,12,13,15,16,17-deca-hydro-2H-cyclo-penta-[α]phenanthren-3(4H,9H,14H)-one], C(31)H(50)O, is a triterpenoid which was isolated from Skimmia laureola. The three six-membered rings adopt chair, slightly distorted half-chair and distorted boat conformations, and the five-membered ring is in an envelope conformation. All the rings are trans fused. In the crystal structure, there is a weak C-H⋯O hydrogen bond.