InChI=1S/C17H18NO4/c1-20-17-11-2-3-18(17)8-10-4-15-16(22-9-21-15)7-13(10)14(17)6-12(19)5-11/h4-5,7-8,12,14,19H,2-3,6,9H2,1H3/q+1