InChI=1S/C21H28O6/c1-9(2)10-13(22)11-12(15(24)14(10)23)21-8-6-7-20(3,4)18(21)17(16(11)26-5)27-19(21)25/h9,16-18,22-24H,6-8H2,1-5H3