InChI=1S/C21H30O4/c1-4-5-6-7-13-8-18(24)20-15-10-14(12-22)17(23)11-16(15)21(2,3)25-19(20)9-13/h8-10,15-17,22-24H,4-7,11-12H2,1-3H3