InChI=1S/C25H38O4/c26-23-19-22(20-24(27)21-23)17-15-13-11-9-7-5-3-1-2-4-6-8-10-12-14-16-18-25(28)29/h2,4,8,10,19-21,26-27H,1,3,5-7,9,11-18H2,(H,28,29)/b4-2+,10-8+