Peripherally-selective inhibitors of dopamine-β-hydroxylase and method of their preparation

A compound of Formula I:

• where R1, R2 and R3 are the same or different and signify hydrogens, halogens, alkyl groups, alkyloxy groups, hydroxy groups, nitro groups, amino groups, alkylcarbonylamino groups, alkylamino groups or dialkylamino groups;
• R4 signifies hydrogen, an alkyl group or an alkylaryl group;
• X signifies CH2, an oxygen atom or a sulphur atom;
• n is 1, 2 or 3, with the proviso that when n is 1, X is not CH2;
• and the individual (R)- and (S)-enantiomers or mixtures of enantiomers and pharmaceutically acceptable salts thereof;
• wherein the term alkyl means hydrocarbon chains, straight or branched, containing from one to six carbon atoms, optionally substituted by aryl groups, alkoxy groups, halogen groups, alkoxycarbonyl groups or hydroxycarbonyl groups;
• the term aryl means a phenyl or naphthyl group, optionally substituted by an alkyloxy group, halogen or nitro group;
• and the term halogen means fluorine, chlorine, bromine or iodine.