N-propylsulfamideis a pharmaceutical intermediate typically used for the preparation of Macitentan, which is an endothelin receptor antagonist (ERA) for the treatment of pulmonary arterial hypertension (PAH).
The discovery of N -[5-(4-bromophenyl)-6-[2-[(5-bromo-2-pyrimidinyl)oxy] ethoxy]-4-pyrimidinyl]- N ′-propylsulfamide (macitentan), an orally active, potent dual endothelin receptor antagonist. 
Improved and single-pot process for the synthesis of macitentan, an endothelin receptor antagonist, via lithium amide-mediated nucleophilic substitutions. 
 M.H.Bolli, et al, J. Med. Chem., 2012, 55(17), pp 7849-7861.