InChI=1S/2C19H18O4/c2*20-16-7-1-14(2-8-16)5-11-18(22)13-19(23)12-6-15-3-9-17(21)10-4-15/h1-5,7-11,20-21H,6,12-13H2;1-5,7-11,13,20-22H,6,12H2/b11-5+;11-5+,18-13-