InChI=1S/C21H31O4/c1-13(23)21(25)10-7-17-16-4-3-14-11-15(24)5-9-20(14,12-22)18(16)6-8-19(17,21)2/h3,15-18,22,25H,4-12H2,1-2H3/t15?,16?,17?,18?,19-,20+,21-/m0/s1