InChI=1S/C21H30O7/c1-12(2)19-18(27-15(5)23)10-17(11-26-14(4)22)9-7-8-13(3)20(25)21(19)28-16(6)24/h9,12,18-19,21H,3,7-8,10-11H2,1-2,4-6H3/b17-9+/t18-,19+,21+/m1/s1