title: 1-Cyclo-pentyl-idene-2-(2,4-dinitro-phenyl)-hydrazine.
abstract: The title compound, C(11)H(12)N(4)O(4), was synthesized by the reaction of (2,4-dinitro-phen-yl)hydrazine with cyclo-penta-none. The cyclo-pentyl fragment is disordered over two sites with occupancies of 0.63 (1) and 0.37 (1). An intra-molecular N-H⋯O hydrogen bond helps to establish the conformation. Pairs of mol-ecules are held together by π-π inter-actions between adjacent benzene rings [centroid-to-centroid distance 3.589 (2) Å].
authors.forename: Ning-Ning
authors.initials: NN
authors.lastname: Ji
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Shi