InChI=1S/C21H24O7/c1-11(2)4-5-15-18(7-13(9-22)16(10-23)20(15)26)28-21(27)19-12(3)6-14(24)8-17(19)25/h4,6-8,22-26H,5,9-10H2,1-3H3