InChI=1S/C25H34O4/c1-18(10-7-8-13-20(3)22(27)28)11-9-12-19(2)14-15-25-23(4,5)16-21(26)17-24(25,6)29-25/h7-15,21,26H,16-17H2,1-6H3,(H,27,28)/b8-7+,11-9+,15-14+,18-10+,19-12-,20-13-