InChI=1S/C21H32O8/c1-10(8-12-6-7-21(3,27)13-5-4-11(2)14(12)13)9-28-20-17(24)15(22)16(23)18(29-20)19(25)26/h8,12-13,15-18,20,22-24,27H,4-7,9H2,1-3H3,(H,25,26)/b10-8+