N-(2-CHLORO-6-METHYLPHENYL)-6-METHYL-3-PYRIDINECARBOXAMIDE HYDRATE - AN ANTICONVULSANT DRUG EXHIBITING SOLID-STATE ROTATIONAL DISORDER

The phenyl ring, the pyridine ring and the carboxamide group are conformationally planar. The Cl atom and the methyl group on the phenyl ring are statistically disordered, by 180-degrees rotation about the N(6)-C(6) linkage, with relative occupancies of 0.7061 (5) and 0.2939 (5) at the major and minor sites, respectively. Hydrogen bonds involving the nitrogen (donor) and the oxygen (acceptor) of the carboxamide moiety with the water oxygen, together with the hydrogen bond between the nitrogen (acceptor) of the pyridine moiety and the water oxygen structurally stabilize the pyridine and carboxamide groups.