InChI=1/C17H20O6/c1-2-13(11-19)14(5-7-18)10-17(22)23-8-6-12-3-4-15(20)16(21)9-12/h2-4,7,9,11,14,20-21H,5-6,8,10H2,1H3/b13-2+