InChI=1S/C21H26O7/c1-26-19-7-12(4-6-16(19)23)3-5-15-10-14(22)11-18(28-15)13-8-17(24)21(25)20(9-13)27-2/h4,6-9,14-15,18,22-25H,3,5,10-11H2,1-2H3