title: 1',5-Dinitro-2'-phenyl-2',3',5',6',7',7a'-hexa-hydro-spiro-[indoline-3,3'-1'H-pyrrolizin]-2-one.
abstract: In the title cyclo-adduct, C(20)H(18)N(4)O(5), the rings of the pyrrolizine system adopt envelope conformations. A centrosymmetric dimer is formed via inter-molecular N-H⋯O hydrogen bonds between the indolinone rings.
authors.affiliation: Department of Chemistry, University of Mazandaran, 47415 Babolsar, Iran.
authors.forename: Yaghoub
authors.initials: Y
authors.lastname: Sarrafi
authors.forename: Kamal
authors.initials: K
authors.lastname: Alimohammadi