InChI=1S/C18H19NO5/c1-24-17-10-13(15(21)11-16(17)22)4-7-18(23)19-9-8-12-2-5-14(20)6-3-12/h2-7,10-11,20-22H,8-9H2,1H3,(H,19,23)/b7-4+