InChI=1S/C22H22O5/c1-15(3-2-14-23)4-10-18-21(26)13-11-19(22(18)27)20(25)12-7-16-5-8-17(24)9-6-16/h4-9,11-14,24,26-27H,2-3,10H2,1H3/b12-7+,15-4+