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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Mefenamic Acid Anti-Inflammatory Drug: Probing Its Polymorphs by Vibrational (IR and Raman) and Solid-State NMR Spectroscopies

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Author(s):
Cunha, Vanessa R. R. [1] ; Izumi, Celly M. S. [1] ; Petersen, Philippe A. D. [2] ; Magalhaes, Alvicler [3] ; Temperini, Marcia L. A. [1] ; Petrilli, Helena M. [2] ; Constantino, Vera R. L. [1]
Total Authors: 7
Affiliation:
[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, BR-05508000 Sao Paulo - Brazil
[2] Univ Sao Paulo, Inst Fis, Dept Fis Mat & Mecan, BR-05315970 Sao Paulo - Brazil
[3] Univ Estadual Campinas, Inst Quim, Dept Quim Inorgan, BR-13083970 Campinas, SP - Brazil
Total Affiliations: 3
Document type: Journal article
Source: Journal of Physical Chemistry B; v. 118, n. 16, p. 4333-4344, APR 24 2014.
Web of Science Citations: 17
Abstract

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 degrees 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 C-13 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. (AU)

FAPESP's process: 11/50318-1 - Development of compounds with pharmacological or medicinal interest and of systems for their transport, detection and recognition in biological media
Grantee:Ana Maria da Costa Ferreira
Support type: Research Projects - Thematic Grants
FAPESP's process: 12/12209-9 - Inorganic carriers of bioactive substances: development, characterization, toxicity evaluation of in vitro delivery and in vivo absorption after oral administration
Grantee:Vanessa Roberta Rodrigues da Cunha
Support type: Scholarships in Brazil - Post-Doctorate