97 research outputs found
Ionophore-based potentiometric PVC membrane sensors for determination of phenobarbitone in its pharmaceutical formulations
The fabrication and development of two polyvinyl chloride (PVC) membrane sensors for assaying phenobarbitone sodium are described. Sensors 1 and 2 were fabricated utilizing - or -cyclodextrin as ionophore in the presence of tridodecylmethylammonium chloride as a membrane additive, and PVC and dioctyl phthalate as plasticizer. The analytical parameters of both sensors were evaluated according to the IUPAC guidelines. The proposed sensors showed rapid, stable anionic response (â59.1 and â62.0 mV per decade) over a relatively wide phenobarbitone concentration range (5.0Ă10â6â1Ă10â2 and 8Ă10â6â1Ă10â2 mol Lâ1) in the pH range of 9â11. The limit of detection was 3.5Ă10â6 and 7.0Ă10â6 mol Lâ1 for sensors 1 and 2, respectively. The fabricated sensors showed high selectivity for phenobarbitone over the investigated foreign species. An average recovery of 2.54 ”g mLâ1 phenobarbitone sodium was 97.4 and 101.1 %, while the mean relative standard deviation was 3.0 and 2.1 %, for sensors 1 and 2, respectively. The results acquired for determination of phenobarbitone in its dosage forms utilizing the proposed sensors are in good agreement with those obtained by the British Pharmacopoeial method
High-performance liquid chromatography and derivative spectrophotometry for simultaneous determination of pravastatin and fenofibrate in the dosage form
High performance liquid chromatography (HPLC) and second-order derivative spectrophotometry have been used for simultaneous determination of pravastatin (PS) and fenofibrate (FF) in pharmaceutical formulations. HPLC separation was performed on a phenyl HYPERSIL C18 column (125 mm 4.6 mm i.d., 5 m particle diameter) in the isocratic mode using a mobile phase acetonitrile/0.1 % diethyl amine (50:50, V/V, pH 4.5) pumped at a flow rate of 1.0 mL minâ1. Measurement was made at 240 nm. Both drugs were well resolved on the stationary phase, with retention times of 2.15 and 5.79 min for PS and FF, respectively. Calibration curves were linear (R = 0.999 for PS and 0.996 for FF) in the concentration range of 5â50 and 20â200 ”g mLâ1 for PS and FF, respectively.
Pravastatin and fenofibrate were quantitated in combined preparations also using the second-order derivative response at 237.6 and 295.1 nm for PS and FF, respectively. Calibration curves were linear, with the correlation coefficient R = 0.999 for pravastatin and fenofibrate, in the concentration range of 5â20 and 3â20 ”g mLâ1 for PS and FF, respectively. Both methods were fully validated and compared; the results confirmed that they were highly suitable for their intended purpose
Protective Effect of Chemically Characterized Polyphenol-Rich Fraction from Apteranthes europaea (Guss.) Murb. subsp. maroccana (Hook.f.) Plowes on Carbon Tetrachloride-Induced Liver Injury in Mice
Apteranthes europaea (Guss.) Murb. subsp. maroccana (Hook.f.) Plowes (A. europaea) is a medicinal plant widely used in traditional medicines to treat various diseases including hepatic pathogenesis. This study was conducted to evaluate the protective effect of chemically characterized polyphenol-rich fraction from A. europaea on carbon tetrachloride-induced liver injury in mice. The chemical characterization of A. europaea polyphenol-rich fraction was carried out using HPLC-DAD (high-performance liquid chromatography (HPLC) with a diode-array detector (DAD)). Carbon tetrachloride (CCl4) was used to induce liver injuries in mice as described in previous works. A polyphenol-rich fraction from A. europaea was used at a dose of 50 mg/Kg to study its hepatoprotective effect. Next, histopathological and biochemical alterations were investigated. The HPLC analysis revealed the presence of several phenolic compounds: gallic acid, methyl gallate, rutin, ferulic acid, and resorcinol. Regarding the mice treated with a polyphenol-rich fraction from A. europaea up to 50 mg/Kg and carbon tetrachloride, no significant biochemical nor histological alterations occurred in their liver; meanwhile, serious biochemical and histopathological changes were noted for liver recovered from the mice treated with carbon tetrachloride only. In conclusion, A. europaea extract is a promising source of hepatoprotective agents against toxic liver injury
4-(4-Bromophenyl)-2-(3-(4-chlorophenyl)-5-{3-[5-methyl-1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl]-1-phenyl-1H-pyrazol-4-yl}-4,5-dihydro-1H-pyrazol-1-yl)-1,3-thiazole
The asymmetric unit of the title compound, C37H28BrClN8S, comprises one molecule. The molecule consists of two ring systems joined by a CâC bond between the dihydropyrazolyl and pyrazolyl rings of the two extended ring systems. The angles between adjacent ring planes of the tolylâtriazolylâpyrazolylâphenyl ring system are 48.2â
(1), 12.3â
(2) and 22.2â
(2)°, respectively, with angles of 19.7â
(1), 5.6â
(2) and 0.9â
(2)° between the rings of the chlorophenylâthiazolylâdihydropyrazolylâbromophenyl set. The pyrazolyl and dihydropyrazolyl rings are inclined at 68.3â
(1)° to one another. In the crystal, CâH...Cl interactions form chains of molecules parallel to the b-axis direction
4-(4-Bromophenyl)-2-(3-(4-bromophenyl)-5-{3-[5-methyl-1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl]-1-phenyl-1H-pyrazol-4-yl}-4,5-dihydro-1H-pyrazol-1-yl)-1,3-thiazole
In the title compound, C37H28Br2N8S, the dihedral angles between the planes of tolylâtriazolylâpyrazolylâphenyl rings are 47.5â
(1), 11.4â
(2) and 22.4â
(2)°, respectively, and the angles between the bromophenylâthiazolylâdihydropyrazolylâbromophenyl rings are 16.0â
(2), 5.1â
(2) and 0.8â
(2)°, respectively. The dihedral angle between the planes of the pyrazolyl and dihydropyrazolyl rings is 67.7â
(1)°. In the crystal, weak CâH...Br interactions form chains of molecules propagating in the [010] direction
4-(4-Bromophenyl)-2-(3-(4-chlorophenyl)-5-{3-[5-methyl-1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl]-1-phenyl-1H-pyrazol-4-yl}-4,5-dihydro-1H-pyrazol-1-yl)-1,3-thiazole
The asymmetric unit of the title compound, C37H28BrClN8S, comprises one molecule. The molecule consists of two ring systems joined by a CâC bond between the dihydropyrazolyl and pyrazolyl rings of the two extended ring systems. The angles between adjacent ring planes of the tolylâtriazolylâpyrazolylâphenyl ring system are 48.2â
(1), 12.3â
(2) and 22.2â
(2)°, respectively, with angles of 19.7â
(1), 5.6â
(2) and 0.9â
(2)° between the rings of the chlorophenylâthiazolylâdihydropyrazolylâbromophenyl set. The pyrazolyl and dihydropyrazolyl rings are inclined at 68.3â
(1)° to one another. In the crystal, CâH...Cl interactions form chains of molecules parallel to the b-axis direction
(E)-1-[5-Methyl-1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl]-3-(4-nitrophenyl)prop-2-en-1-one
The title compound, C19H16N4O3, crystallizes with two molecules (A and B) in the asymmetric unit. In molecule A, the dihedral angles between the triazole ring and the toluyl and nitrobenzene rings are 62.68â
(16) and 10.77â
(15)°, respectively. The corresponding data for molecule B are 68.61â
(17) and 15.59â
(15)°, respectively. In the crystal, the B molecules are linked by CâH...N hydrogen bonds to generate [001] chains. Weak CâH...Ï(benzene) and NâO...Ï(triazole) contacts are also present
5-Methyl-N'-(5-methyl-1-phenyl-1H-1,2,3-triazole-4-carbonyl)-1-phenyl-1H-1,2,3-triazole-4-carbohydrazide
The asymmetric unit of the title compound, C20H18N8O2, comprises one complete molecule and a half molecule completed by crystallographic twofold symmetry leading to Z = 12. The dihedral angles between the planes of the linked phenyl and methyltriazolyl groups are 69.48â
(5) and 44.85â
(9)° for the first molecule and 42.88â
(9)° for the second. The conformations of the diformyl hydrazyl groups of the molecules are similar as indicated by CâNâNâC torsion angles of â83.4â
(2) and â86.4â
(3)°. In the crystal, neighbouring molecules are linked by pairs of NâH...O hydrogen bonds to form independent columns propagating parallel to the c-axis direction
1-{2-Anilino-4-methyl-5-[5-methyl-1-(4-methylphenyl)-1H-1,2,3-triazole-4-carbonyl]thiophen-3-yl}ethanone
In the title compound, C24H22N4O2S, the dihedral angle between the triazole and thiophene rings is 4.83â
(14)°. The dihedral angles between the triazole and tolyl rings and between the thiophene and phenyl rings are 48.42â
(16) and 9.23â
(13)°, respectively. An intramolecular NâH...O hydrogen bond closes an S(6) loop. In the crystal, molecules are stacked parallel to the a-axis direction with weak ÏâÏ interactions between adjacent thiophenyl and triazolyl groups within the stack [centroidâcentroid separation = 3.9811â
(16)â
Ă
]
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