Cyanuric acid (CA) forms a 2: 1 hydrogen-bonded adduct with 4, 4′-bipyridyl (BP) when co- crystallized from a methanol solution and a 1: 1 adduct from an aqueous solution. The sheet structure of the 2: 1 adduct involves cyclic hydrogen bonds between the amide units of adjacent CA molecules and N–H⋯ N bonds between CA and BP. The 1: 1 adduct crystallized from water has a chain structure with single N–H⋯ O hydrogen bonds ...
