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