| 19560892 |
Sampath A, Reddy AR, Yakambaram B, Thirupathi A, Prabhakar M, Reddy PP, Reddy VP: Identification and characterization of potential impurities of valsartan, AT1 receptor antagonist. J Pharm Biomed Anal. 2009 Oct 15;50(3):405-12. Epub 2009 May 30.
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-yl methyl] amine (impurity I); (S)-N-(1-carboxy-2-methylprop-1-yl)-N-(5-phenylthio) pentanoyl-N-[2'-(1H-te trazol-5-yl)-biphenyl-4-ylmethyl] amine (impurity II); (S)-N-(1-carboxy-2-methylprop-1-yl)-N-(5-phenyl) pentanoyl-N-[2'-(1H-tetraz ol-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-tetra zol-5-yl)-biphenyl-4-ylmethyl] amine (impurity V). |
1(0,0,0,1) |