This work deals with the spectroscopic (supported by quantum chemistry calculations), structural, and morphological characterization of mefenamic acid (2-[(2,3-(dimethylphenyl)amino] benzoic acid) polymorphs, known as forms I and II. Polymorph I was obtained by recrystallization in ethanol, while form II was reached by heating form I up to 175 °C, to promote the solid phase transition. Experimental and theoretical vibrational band assignments were performed considering the presence of centrosymmetric dimers. Besides band shifts in the 3345-3310 cm(-1) range, important vibrational modes to distinguish the polymorphs are related to out-of-phase and in-phase N-H bending at 1582 (Raman)/1577 (IR) cm(-1) and 1575 (Raman)/1568 (IR) cm(-1) for forms I and II, respectively. In IR spectra, bands assigned to N-H bending out of plane are observed at 626 and 575 cm(-1) for polymorphs I and II, respectively. Solid-state (13)C NMR spectra pointed out distinct chemical shifts for the dimethylphenyl group: 135.8 to 127.6 ppm (carbon bonded to N) and 139.4 to 143.3 ppm (carbon bonded to methyl group) for forms I and II, respectively.
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JAMA Pediatr
December 2024
Department of Pharmacy, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
Importance: Gestational exposure to nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk of adverse fetal kidney outcomes. However, details regarding timing, specific NSAIDs, and long-term childhood kidney outcomes are limited.
Objective: To evaluate the association between gestational exposure to NSAIDs and the risk of chronic kidney disease (CKD) in childhood.
Chem Commun (Camb)
December 2024
EPSRC Future Continuous Manufacturing and Advanced Crystallisation Research Hub, University of Strathclyde, 99 George Street, Glasgow, G1 1RD, UK.
Application of multivariate curve resolution to non-invasive Raman spectra has been investigated for rapid on-line analysis of crystallisation processes and high-throughput screening. Exploring quantification of mefenamic acid solid forms (form I, form II, and dimethylformamide solvate) from the Raman spectra indicated excellent agreement with off-line X-ray analysis.
View Article and Find Full Text PDFBr J Pharmacol
November 2024
Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada.
Environ Sci Pollut Res Int
November 2024
BASF SE, Agricultural Solutions - Ecotoxicology, Speyerer Strasse 2, 67117, Limburgerhof, Germany.
The Xenopus Eleutheroembryonic Thyroid Assay (XETA, OECD TG 248) was established as an alternative to the Amphibian Metamorphosis Assay (AMA, OECD TG 231) for the analysis of (anti-)thyroid activity of chemicals. The XETA is a New Approach Method (NAM) since the embryonic life stages used in the assay are not yet feeding independently, which renders the assay to be considered a non-animal test under many national laws. Physiologically, the used embryos are not fully developed yet, and thus there are limitations to the XETA for detecting certain mechanisms along the hypothalamic-pituitary-thyroid (HPT) axis.
View Article and Find Full Text PDFPharmaceuticals (Basel)
October 2024
Department of Physical and Colloidal Chemistry, Faculty of Pharmacy, "Carol Davila" University of Medicine and Pharmacy, 6 Traian Vuia Str., 020956 Bucharest, Romania.
: The study explores the potential of various deep eutectic solvents (DESs) to serve as drug delivery systems and pharmaceutical excipients. The research focuses on two primary objectives: evaluating the ability of the selected DES systems to enhance the solubility of two poorly water-soluble model drugs (IBU and MFA), and evaluating their physicochemical properties, including density, viscosity, flow behavior, surface tension, thermal stability, and water dilution effects, to determine their suitability for pharmaceutical applications. : A range of DES systems containing pharmaceutically acceptable constituents was explored, encompassing organic acid-based, sugar- and sugar alcohol-based, and hydrophobic systems, as well as menthol (MNT)-based DES systems with common pharmaceutical excipients.
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