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Receptor Autoradiography Protocol for the Localized Visualization of Angiotensin II Receptors
Published on: June 7, 2016
Identification and characterization of potential impurities of valsartan, AT1 receptor antagonist
A Sampath1, A Raghupathi Reddy, B Yakambaram
1Department of Research and Development, Integrated Product Development, Innovation Plaza, Dr. Reddy's Laboratories Ltd., Survey Nos. 42, 45, 46 & 54, Bachupally, Qutubullapur, R.R. Dist-500072, AP, India.
Abstract:
Five impurities (related substances) were detected during the impurity profile study of an antihypertensive drug substance, valsartan. A simple gradient high performance liquid chromatographic method (HPLC) and liquid chromatography-mass spectrometry (LC-MS) were used for the detection. Based on the spectral data (IR, NMR and MS) followed by synthesis, these impurities were characterized as (S)-N-(1-carboxy-2-methylprop-1-yl)-N-[2'-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]amine (impurity I); (S)-N-(1-carboxy-2-methylprop-1-yl)-N-(5-phenylthio)pentanoyl-N-[2'-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]amine (impurity II); (S)-N-(1-carboxy-2-methylprop-1-yl)-N-(5-phenyl)pentanoyl-N-[2'-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]amine (impurity III); (S)-N-(1-carboxy-2-methylprop-1-yl)-N-4-pentenoyl-N-[2'-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]amine (impurity IV); (S)-N-(1-carboxy-2-methylprop-1-yl)-N-(5-hydroxy)pentanoyl-N-[2'-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]amine (impurity V).
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