4-(tert-butyl)-N-(6-(2-hydroxyethoxy)-5-(2-hydroxyphenoxy)-[2,2'-bipyrimidin]-4-yl)benzenesulfonamide; 4-(1,1-Dimethylethyl)-N-[6-(2-hydroxyethoxy)-5-(2-hydroxyphenoxy)[2,2’-bipyrimidin]-4-yl]benzenesulfonamide; Ro 47-8634; Bosentan O-Desmethyl Impurity
