InChI=1S/C21H30O4/c1-13(12-22)5-4-6-14(2)15-9-10-21(3)17(15)11-16-18(23)7-8-19(24)20(16)25-21/h5-6,15,17,19,22,24H,4,7-12H2,1-3H3/b13-5+,14-6-