InChI=1S/C21H28O6/c1-9-6-13(26-5)19(25)21(4)11(9)7-14-20(3)12(8-15(22)27-14)10(2)16(23)17(24)18(20)21/h6,9,11-12,14,16-18,23-24H,2,7-8H2,1,3-5H3