| abstract |
A process for preparing a 5- (2 - {[6- (2,2-difluoro-2-phenylethoxy) hexyl] amino} -1-hydroxyethyl) -8-hydroxyquinoline-2 (1H) -one compound of formula ( I), or a pharmaceutically acceptable salt thereof, process comprising: a) reacting, in xylene as a solvent, a compound of formula (V) where P1 and P2 represent hydroxy protecting groups and L is a leaving group, with 6 - (2,2-Difluoro-2-phenylethoxy) hexane-1-amine of formula (IV), to give a compound of formula (III) b) carry out a deprotection step P1 and a deprotection stage P2, for remove protective groups P1 and P2 giving rise to compound (I). |