InChI=1S/C21H22O7/c1-27-20-9-13(4-7-17(20)24)3-6-15(22)11-16(23)12-19(26)14-5-8-18(25)21(10-14)28-2/h3-10,19,24-26H,11-12H2,1-2H3/b6-3-