InChI=1S/C26H30O4/c1-18(2)13-15-26(16-14-19(3)4)23(28)17-22(30-5)24(25(26)29)21(27)12-11-20-9-7-6-8-10-20/h6-14,17,27H,15-16H2,1-5H3/b12-11+,24-21+