InChI=1S/C21H22O5/c1-14(6-9-21(2,3)13-22)7-10-25-20-15-4-5-19(23)26-18(15)12-17-16(20)8-11-24-17/h4-5,7-8,11-13H,6,9-10H2,1-3H3/b14-7+