The invention relates to quinoxalinone derivatives of general Formula (I)
and their use as active ingredients in the preparation of pharmaceutical
compositions. The invention also concerns related aspects including
processes for the preparation of the compounds, pharmaceutical
compositions containing one or more of those compounds and especially
their use as orexin receptor antagonists. General Formula (I) wherein X
and R.sup.1-R.sup.9 are as defined in the description ##STR00001##