title: 2-[2,6-Bis(pyrazin-2-yl)pyridin-4-yl]benzoic acid.
abstract: In the title compound, C20H13N5O2, the two pyrazine rings are nearly coplanar with the central pyridine ring, forming dihedral angles of 2.21 (9) and 4.57 (9)°. In contrast, the strong steric hindrance caused by the ortho-carboxyl group on the phenyl ring makes this ring rotate out of the attached pyridine ring plane by 52.60 (9)°. The carboxyl group is twisted from the phenyl ring by 22.6 (1)°. In the crystal, aromatic π-π stacking inter-actions [centroid-centroid distances = 3.9186 (4) and 3.9794 (5) Å] occur between the anti-parallel mol-ecules, generating infinite chains along [100]. O-H⋯O hydrogen bonds connect the chains, leading to the formation of a two-dimensional supra-molecular network parallel to (010). Inter-molecular C-H⋯N hydrogen bonds are also observed.
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Shuai
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.
authors.forename: Xiang-Yang
authors.initials: XY
authors.lastname: Wang
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.
authors.forename: Jing-Wei
authors.initials: JW
authors.lastname: Dai
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Wu