(3E)-1-(3-nitrophenyl)-3-(piperidin-1-ylmethylene)pyrrolidine-2,5-dione 2,5-pyrrolidinedione, 1-(3-nitrophenyl)-3-(1-piperidinylmethylene)-, (3E)- InChI=1/C16H17N3O4/c20-15-9-12(11-17-7-2-1-3-8-17)16(21)18(15)13-5-4-6-14(10-13)19(22)23/h4-6,10-11H,1-3,7-9H2/b12-11