Process for introduction of hydroxyethoxy side chain in bosentan
摘要
<p>The present invention relates to an improved process for the preparation of bosentan. In particular it relates to a process for preparing bosentan substantially free from the dirner impurity of formula (II) and the 6-hydroxy impurity of formula (III). The invention also relates to a pharmaceutical composition comprising bosentan and its use in the treatment of endothelin-receptor mediated disorders.</p>