Molecular structures of metal complexes with mefenamic acid

Area of Science:

• Materials Science
• Analytical Chemistry
• Computational Chemistry

Background:

• Mefenamic acid is a non-steroidal anti-inflammatory drug.
• Understanding the coordination chemistry of mefenamic acid with metal ions is crucial for developing new pharmaceutical formulations or analytical methods.

Purpose of the Study:

• To investigate the structural properties of sodium (Na) and calcium (Ca) complexes of mefenamic acid.
• To elucidate the coordination mode of metal ions with mefenamic acid using spectroscopic and diffraction techniques.
• To support experimental findings with theoretical calculations.

Main Methods:

• Infrared (IR) spectroscopy in the 4000-400 cm(-1) region.
• X-ray powder diffraction (XRPD) analysis.
• Molecular mechanics calculations.
• Conformational analysis.

Main Results:

• IR spectra showed characteristic bands for carboxylate stretching vibrations (v(as)(COO)- and v(s)(COO)-) at approximately 1580 cm(-1) and 1390-1400 cm(-1), respectively.
• XRPD patterns supported the structural models derived from IR spectroscopy.
• NH deformation vibrations remained unchanged, indicating no direct interaction at this site.
• Molecular mechanics and conformational analysis helped determine atomic planes and assign peaks in the XRPD patterns.

Conclusions:

• Metal atoms (Na and Ca) are coordinated to the carboxyl group of mefenamic acid.
• The combined experimental and theoretical approach provides robust evidence for the structure of these metal complexes.
• This study contributes to the understanding of mefenamic acid's coordination chemistry.