High performance liquid chromatographic assay of amlodipine, valsartan and hydrochlorothiazide simultaneously and its application to pharmaceuticals, urine and plasma analysis.

A Simple, Specific, Precise, Accurate, Linear, Rugged, Robust High Performance Liquid Chromatographic method of analysis for simultaneous determination of assay of Amlodipine, Valsartan and Hydrochlorothiazide drugs in the pharmaceuticals tablet formulations using Pioglitazone as a common internal standard was developed and validated. The assay was accomplished using a mixture of acetonitrile & methanol in the volume ratio of 20:80 v/v (mobile phase B) and Ammonium acetate buffer (Mobile phase A) in gradient flow as mobile phase on an Hibar RP-18e, 250 × 4.6 mm, 5µ as chromatographic column at a flow rate of 1.300 mLmin-1, injection volume 10 µL and at a wavelength 235 nm with UV detector. Linearity of the analytical method was evaluated at a concentration range of 2.5-45.3 µg/ml for Amlodipine, 32.0-720.1 µg/ml for valsartan and 5.0-112.6 µg/ml for Hydrochlorothiazide respectively with Correlation coefficient (r) value more than 0.9997. The limit of detection (LOD) for Amlodipine, Valsartan and Hydrochlorothiazide was found to be 1.1 µg/ml, 8.0 µg/ml & 1.0 µg/ml respectively. Specificity, Method Precision, System Precision, Ruggedness, Robustness, Recovery, Stability of analytical solution, Filter paper selection study, Stress testing (Force Degradation) at various conditions were performed as per the ICH (Q2) recommendations. The chromatographic method may also be applied for simultaneous estimation of analytes in plasma and urine.

An Operationally Simple and Efficient Synthesis of 7-Benzylidene-substitutedphenyl- 3,3a,4,5,6,7-hexahydro-2H-indazole by Grinding Method.

BACKGROUND: An eco-friendly, operationally simple and efficient reaction is shown between various 2,6-bis-(substituted-benzylidene)-cyclohexanones and differently substituted hydrazine in the presence of acetic acid. METHODS: The reaction between various 2,6-bis-(substituted-benzylidene)-cyclohexanones and differently substituted hydrazine in the presence of acetic acid afforded 7-Benzylidene-substituted-phenyl-3,3a,4,5,6,7- hexahydro-2H-indazole in 74 to 92 % yield in short reaction time using the grindstone technique. RESULTS AND DISCUSSION: The notable advantages of this method include mild synthetic conditions, weak acid catalysis, and non-hazardous solvent which make this method environmentally safer. CONCLUSION: In conclusion, we have developed an efficient, simple and eco-friendly method for the synthesis of 7-Benzylidene-substituted-phenyl-3,3a,4,5,6,7-hexahydro-2H-indazole by grinding technique. The notable benefits of this method are waste minimization, no organic solvent required, simple procedure, easy work-up, and clean reaction profile.