InChI=1S/C20H26O4/c1-4-17(2)6-5-13-12(10-17)9-14-15-18(3,16(21)24-14)20(22)8-7-19(13,15)11-23-20/h4,9,13-15,22H,1,5-8,10-11H2,2-3H3