Solid-State Studies of the Triclinic (Z′=2) Antiprotozoal Drug Ternidazole

• Published in: Journal of pharmaceutical sciences Vol. 100; no. 6; pp. 2258 - 2266
• Main Authors: Mahé, Nathalie, Perrin, Marc-Antoine, Barrio, Maria, Nicolaï, Béatrice, Rietveld, Ivo B., Tamarit, Josep-Lluís, Céolin, René
• Format: Journal Article
• Language: English
• Published: Hoboken Elsevier Inc 01.06.2011; Wiley Subscription Services, Inc., A Wiley Company; Wiley; American Pharmaceutical Association; Elsevier Limited
• Subjects: Antiprotozoal Agents - chemistry; Biological and medical sciences; calorimetry; Calorimetry, Differential Scanning; Chemical Sciences; crystal structure; Crystallization; density; General pharmacology; glass transition; Hydrogen Bonding; Medical sciences; Molecular Conformation; nitroimidazole; Ornidazole - analogs & derivatives; Ornidazole - chemistry; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Phase Transition; physical characterization; polymorphism; pressure-temperature phase diagram; Surface Properties; thermal expansion; Thermodynamics; X-Ray Diffraction; calorimetry; physical characterization; density; thermal expansion; nitroimidazole; crystal structure; thermodynamics; pressure–temperature phase diagram; polymorphism; glass transition; Drug; Nitro compound; Imidazole derivatives; Temperature; Pharmaceutical technology; pressure―temperature phase diagram; Phase diagram; Ternidazole; Density; Pressure; Physical properties; Glass transition; Antiprotozoal agent; Solid state; Thermodynamics; Parasiticide; Calorimetry; Polymorphism; Crystalline structure
• ISSN: 0022-3549; 1520-6017
• DOI: 10.1002/jps.22460

The solid-state properties of antiprotozoal ternidazole (3-(2-methyl-5-nitroimidazol-1-yl)-propan-1-ol) have been studied. Crystals are triclinic in the temperature interval between 100 and 333K (melting point) with two different molecular conformations present in the asymmetric unit (Z′=2) and two of each conformer make up a tetramer held together by hydrogen bonding. Its melting enthalpy at 333K is 25.65 (±1.29) kJ·mol−1. Linear plots were obtained for the melting temperature versus pressure (dP/dT=5.67 (±0.08) MPa·K−1] and the glass transition versus pressure [dP/dT=7.73 (±1.76) MPa·K−1]. No crystalline polymorphism could be detected; thus, the single-crystal structure that has been found is most likely the stable one.