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1.
Molecules ; 26(5)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803210

RESUMO

Recently, the design of new biological metal-ligand complexes has gained a special interest all over the world. In this research, new series of mixed ligand complexes from meloxicam (H2mel) and glycine (Gly) were synthesized. Structures of the compounds were investigated employing elemental analyses, infrared, electronic absorption, 1H NMR, thermal analyses, effective magnetic moment and conductivity. The estimated molar conductivity of the compounds in 1 × 10-3 M DMF solution indicates the non-electrolyte existence of the examined complexes. Additionally, the effective magnetic moment values refer to the complexes found as octahedral molecular geometry. The data of the infrared spectra showed the chelation of H2mel and Gly with metal ions from amide oxygen and nitrogen of the thyizol groups of H2mel and through nitrogen of the amide group and oxygen of the carboxylic group for Gly. Thermal analyses indicated that the new complexes have good thermal stability and initially lose hydration water molecules followed by coordinated water molecules, Gly and H2mel. The kinetic parameters were calculated graphically using Coats-Redfern and Horowitz-Metzeger methods at n = 1 and n ≠ 1. The density functional theory (DFT) calculations were performed at B3LYP levels. The optimized geometry of the ligand and its complexes were obtained based on the optimized structures. The data indicated that the complexes are soft with η value in the range 0.114 to 0.086, while η = 0.140 for free H2mel. The new prepared complexes were investigated as antibacterial and antifungal agents against some phyto- and human pathogens and the minimum inhibitory concentration (MIC) data showed that complex (A) has the lowest MIC for Listeria and E. coli (10.8 µg/mL).


Assuntos
Meloxicam/química , Meloxicam/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Complexos de Coordenação/química , Escherichia coli/efeitos dos fármacos , Íons , Cinética , Ligantes , Espectroscopia de Ressonância Magnética/métodos , Meloxicam/síntese química , Metais/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Bases de Schiff/química , Espectrofotometria Infravermelho/métodos , Termodinâmica
2.
Drug Dev Ind Pharm ; 46(7): 1092-1099, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32475190

RESUMO

Meloxicam (MLX) is a non-steroidal anti-inflammatory which is practically insoluble in water, requiring high concentrations to reach therapeutic levels and causing frequently gastrointestinal effects. In this way, the aim of this study was to synthesize two eutectic mixtures of MLX with mandelic acid (MND) and saccharin (SAC) by liquid-assisted grinding resulting in a multicomponent material with enhanced solubility. Mixtures were studied in different stoichiometric and eutectic point was found for each eutectic by Binary phase diagram and Tamman's triangle, with 0.33 molar fraction of MLX for SAC and MND. Eutectics were characterized by thermoanalytical techniques (TG-DSC, EGA, DSC, and DSC microscopy), infrared spectroscopy, and X-ray powder diffraction. Thermal behavior was studied and videos of the materials being heated were available. A polymorphic transition was discovered and studied for MLX-MND eutectic. Each new system was evaluated by solubility, dissolution, and hygroscopicity tests. Eutectics showed an increase in solubility of 1.7× (MLX-MND1), 3.1× (MLX-MND2), and 1.3× (MLX-SAC) with slower dissolution profile when compared with MLX. All new solid forms showed high hygroscopicity at 98% relative humidity with 27.9 and 58.9% increase in mass at day four for MLX-SAC and MLX-MND, deliquescence occurs at day 6. The experiments and analysis in this study help to understand the behavior of eutectics and evaluate them as an approach to modify properties in drugs.


Assuntos
Ácidos Mandélicos , Meloxicam/síntese química , Sacarina , Meloxicam/química , Solubilidade , Difração de Raios X
3.
Pharm Dev Technol ; 25(7): 882-891, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32281899

RESUMO

Meloxicam is a widely used non-steroidal anti-inflammatory agent. However, its erratic and poor dissolution delays its onset of action. Dissolution enhancement of such medicine is essential to obtain rapid pain relief. Amino acids showed high potential to enhance the dissolution rate of drugs after co-processing. Accordingly, the objective of this work was to investigate the effect of co-processing of meloxicam with arginine, cysteine, and glycine on its crystalline structure and dissolution rate. Meloxicam was mixed with increasing molar ratios of amino acids before acetone-assisted kneading. The resulting products were examined using Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction in addition to monitoring the dissolution behavior. Combined instrumental analysis indicated salt formation with a possibility of further crystalline changes at high concentration of amino acids. Salt formation and crystalline structure modification were associated with a significant increase in the dissolution rate of meloxicam. The study introduced amino acids as potential excipients for enhanced dissolution of meloxicam after wet co-processing.


Assuntos
Acetona/síntese química , Aminoácidos/síntese química , Química Farmacêutica/métodos , Meloxicam/síntese química , Acetona/farmacocinética , Aminoácidos/farmacocinética , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/farmacocinética , Meloxicam/farmacocinética , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos
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