InChI=1S/C20H28O2/c1-5-6-7-14-11-17(21)19-15-10-13(2)8-9-16(15)20(3,4)22-18(19)12-14/h10-12,15-16,21H,5-9H2,1-4H3/t15-,16-/m1/s1