Abstract

Isolation By Preparative HPLC And Characterization Of Process-Related Impurities In Tebuconazole

Author(s): S.G.Hiriyanna, K.Sreedhar, V.Dhayanithi, K.V.S.R.Krishna Reddy, Gopal Vaidyanathan, K.Basavaiah

Two unknown impurities in tebuconazole bulk material, at levels ranging from 0.07% to 0.3% were detected by a gradient RPHPLC and gas chromatography (GC). The impurity at 0.3% level was isolated from a crude sample of tebuconazole using reverse phase preparative LC. The level of the other impurity in crude sample of tebuconazole was less than 0.1% and hence it was not isolated. Rather this impurity has been characterized by LC-MS/MS and GC-MS experimental data. The impurity isolated by preparative LC was characterized by NMR, MS experimental data. Based on the results obtained from different spectroscopic experiments, these impurities have been characterized as 3-((4H-1,2,4- triazol-4-yl)methyl) methyl)-1-(4-chlorophenyl)-4,4-dimethylpentan-3-ol. and 3-((1H-1,2,4-triazol-1-yl)methyl)-4,4-dimethyl-1-phenylpentan-3-ol. Formation of these impurities also discussed in details.