InChI=1S/C21H26O4/c1-21(2,3)17-9-4-15(5-10-17)6-11-18(22)14-25-19-12-7-16(8-13-19)20(23)24/h4-5,7-10,12-13,18,22H,6,11,14H2,1-3H3,(H,23,24)