Solution growth and thermal treatment of crystals lead to two new forms of 2-((2, 6-dimethylphenyl)amino)benzoic acid. Issue 28 (24th April 2018)

• Record Type: Journal Article
• Authors: Hu, Rong; Zhoujin, Yunping; Liu, Meng; Zhang, Mingtao; Parkin, Sean; Zhou, Panpan; Wang, Jianzhi; Yu, Faquan; Long, Sihui
• Is Part Of: RSC advances. Volume 8:Issue 28(2018)
• Page Start: 15459
• Page End: 15470
• Publication Date: 2018-04-24
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7ra13353g
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Two new forms of a potential non-steroidal anti-inflammatory and thyroid drug, 2-((2, 6-dimethylphenyl)amino)benzoic acid were discovered and investigated experimentally and theoretically. Abstract : We report the discovery of two new forms (II andIII ) of a potential non-steroidal anti-inflammatory and thyroid drug, 2-((2, 6-dimethylphenyl)amino)benzoic acid (HDMPA) through solution growth and thermal treatment of crystals. FormII has been discovered through crystal growth in a variety of solvents, and characterized by single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), FT-IR, and Raman spectroscopy. FormII converts into formIII upon thermal treatment, as indicated by the phase behavior study of formII with differential scanning calorimetry (DSC). FormIII has been characterized by IR, Raman and PXRD. Conformational flexibility of the molecule seems to lead to the polymorphism of the system. A conformational scan shows the conformational minima correspond to the conformers in the polymorphs. Lattice energy calculations show energies of −48.14 and −50.31 kcal mol −1 for formsI andII, providing information on the relative stability for each form. Hirshfeld analysis revealed that intermolecular interactions such as C⋯C, H⋯H, C⋯H, and H⋯O contribute to the stability of the crystal forms.