title: N,N',N''-Triphenyl-guanidinium 5-nitro-2,4-dioxo-1,2,3,4-tetra-hydro-pyrimidin-1-ide.
abstract: In the title compound, C(19)H(18)N(3) (+.)C(4)H(2)N(3)O(4) (-), the dihedral angles between the phenyl rings and the plane defined by the central guanidinium fragment are in the range 41.3 (1)-66.6 (1)°. The pyrimidine ring of the anion is distorted towards a boat conformation and the nitro group is rotated 11.4 (2)° out of the uracil plane. Hydrogen bonds assemble the ions in infinite helical chains along the b axis.
authors.affiliation: CEMDRX, Physics Department, University of Coimbra, P-3004-516 Coimbra, Portugal.
authors.forename: P S
authors.initials: PS
authors.lastname: Pereira Silva
authors.forename: S R
authors.initials: SR
authors.lastname: Domingos
authors.forename: M
authors.initials: M
authors.lastname: Ramos Silva
authors.forename: J A
authors.initials: JA
authors.lastname: Paixão
authors.forename: A
authors.initials: A
authors.lastname: Matos Beja