2H-benzimidazoles (isobenzimidazoles). Part 7. A new route to triclabendazole [5-chloro-6-(2,3-dichlorophenoxy)-2-methylthio-1H-benzimidazole] and congeneric benzimidazoles
作者:Brian Iddon、Peter Kutschy、Andrew G. Robinson、Hans Suschitzky、Walter Kramer、Franz A. Neugebauer
DOI:10.1039/p19920003129
日期:——
A new synthesis of the selective anthelmintic agent triclabendazole 7 from the readily available 5,6-dichloro-2H-benzimidazole-2-spirocyclohexane 2 by simple steps is described. Analogous benzimidazoles difficult to prepare by conventional methods are similarly obtained. Triclabendazole can exist as a low-melting metastable solid (m.p. 85-90-degrees-C) convertible by heating or recrystallisation from ethanol into its stable form (m.p. 1 76-1 78-degrees-C).