InChI=1S/C18H22O3/c1-11-8-9-15-17(12(2)10-13(3)18(15)21)14(11)6-4-5-7-16(19)20/h4-9,12-13,18,21H,10H2,1-3H3,(H,19,20)/b6-4+,7-5+