InChI=1S/C20H28O4/c1-13-4-7-16-19(2,10-8-17(22)20(16,3)12-21)15(13)6-5-14-9-11-24-18(14)23/h5,9,11,15-17,21-22H,1,4,6-8,10,12H2,2-3H3