Two pseudo-enantiomeric forms of N-benzyl-4-hydroxy-1-methyl-2,2-dioxo-1H-2λ(6),1-benzothiazine-3-carboxamide and their analgesic properties

Autor: Vyacheslav N. Baumer, Igor V. Ukrainets, Svitlana V. Shishkina, L. A. Petrushova, O. V. Gorokhova, Galina Sim
Rok vydání: 2016
Předmět:
Zdroj: Acta crystallographica. Section C, Structural chemistry. 72(Pt 5)
ISSN: 2053-2296
Popis: The fact that molecular crystals exist as different polymorphic modifications and the identification of as many polymorphs as possible are important considerations for the pharmaceutic industry. The molecule ofN-benzyl-4-hydroxy-1-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxamide, C17H16N2O4S, does not contain a stereogenic atom, but intramolecular hydrogen-bonding interactions engender enantiomeric chiral conformations as a labile racemic mixture. The title compound crystallized in a solvent-dependent single chiral conformation within one of two conformationally polymorphicP212121orthorhombic chiral crystals (denoted formsAandB). Each of these pseudo-enantiomorphic crystals contains one of two pseudo-enantiomeric diastereomers. FormAwas obtained from methylene chloride and formBcan be crystallized fromN,N-dimethylformamide, ethanol, ethyl acetate or xylene. Pharmacological studies with solid–particulate suspensions have shown that crystalline formAexhibits an almost fourfold higher antinociceptive activity compared to formB.
Databáze: OpenAIRE