title: The behavior of Gliclazide in solution and in the solid state: a case of organic compound presenting a solid-solution structure.
abstract: The structure of the hypoglycemic agent Gliclazide has been studied by (1)H, (13)C, and (15)N NMR in solution (CDCl(3) and DMSO-d(6)) and in the solid state. In the solid state, the compound crystallizes as an EZ isomer without dynamic properties. In CDCl(3) solution, the structure is still EZ but with a slow nitrogen inversion about the pyrrolidine nitrogen: two invertomers have been observed and characterized. In DMSO-d(6), the rate is faster and only averaged signals were observed. GIAO calculated absolute shieldings were used to confirm the nature of the observed species. In the solid state, Gliclazide presents the phenomenon of solid-solution with two disordered conformations present in the crystal at a 90:10 ratio.
authors.affiliation: Departamento de Química Orgánica y Bio-Orgánica, Facultad de Ciencias, UNED, Senda del Rey 9, E-28040 Madrid, Spain. dsanta@ccia.uned.es
authors.forename: Dolores
authors.initials: D
authors.lastname: Santa María
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Claramunt
authors.forename: Ibon
authors.initials: I
authors.lastname: Alkorta
authors.forename: José
authors.initials: J
authors.lastname: Elguero
mesh_terms: D018360:Crystallography, X-Ray; D005907:Gliclazide / Q000737:chemistry*; D007004:Hypoglycemic Agents / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D008958:Models, Molecular; D015394:Molecular Structure; D012015:Reference Standards; D012996:Solutions; D013237:Stereoisomerism
chemical_list: D007004:Hypoglycemic Agents; D012996:Solutions; D005907:Gliclazide