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Updated: May 25, 2026

Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
Acridin-10-ium 6-carb-oxy-pyridine-2-carboxyl-ate
1School of Applied Chemical Engineering, The Research Institute of Catalysis, Chonnam National University, Gwangju 500-757, Republic of Korea.
Abstract:
The title compound, C(13)H(10)N(+)·C(7)H(4)NO(4) (-), consists of a protonated acridinium cation and a 6-carb-oxy-pyridine-2-carboxyl-ate monoanion. The carboxyl-ate group of the anion appears to be delocalized on the basis of the nearly equivalent C-O bond lengths. In the crystal, the anions are connected by strong O-H⋯O hydrogen bonds, forming chains along the b axis. The acridinium cations are linked to the anionic chains by strong N-H⋯O hydrogen bonds between the carboxyl-ate group of the anion and the N-H group of the cation. Along the b axis, successive chains stack in opposite directions. Weak inter-molecular C-H⋯O hydrogen bonds further stabilize the crystal structure.
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