Comprehensive Update on Synthetic Aspects of Bosentan Derivatives

Abstract

Abstract: Bosentan and its analogues have been first disclosed in US patent No.5, 292,740 in the year 1994 as endothelin (ET) receptor antagonist. Bosentan synthesis has been reported by employing different methods from the reaction between (4,6-dichloro-5-(2-methoxyphenoxy)-2,2'-bipyrimidine and 4-(tert-butyl) benzenesulfonamide and 4-(tert-butyl)-N-(6-chloro-5-(2-methoxy phenoxy)-[2,2'-bipyrimidin]-4-yl) benzenesulfonamide in the form of different salt like potassium salt, ammonium salt ,sodium salt and isolated as free, on its reaction with ethylene glycol. Various modifications have been observed in the chemistry of the intermediates synthesis of the involved, particularly coupling chemistry to afford bosentan derivatives in high purity and yield.