InChI=1S/C25H24O6/c1-12(2)5-7-15-17(27)11-20-21(23(15)28)24(29)22-19(9-13(3)4)30-18-10-14(26)6-8-16(18)25(22)31-20/h5-12,19,26-28H,1-4H3/b7-5+