InChI=1S/C20H24O7/c1-26-17-5-11(3-4-15(17)23)19-13-7-16(24)18(27-2)6-12(13)8-20(25,10-22)14(19)9-21/h3-7,14,19,21-25H,8-10H2,1-2H3