3-Amino-2-hydroxypropoxyaryl imidazole derivatives

A compound of the formula ##STR121## wherein R and R.sub.1 are independently selected from hydrogen and heterocyclic group having 5-6 ring atoms, one of which is the hetero atom O, S or N such that only one of R and R.sub.1 is hydrogen, R.sub.2 is selected from hydrogen, C.sub.1 -C.sub.10 linear or branched alkyl, hydroxy C.sub.1 -C.sub.10 linear or

• branched alkyl and C.sub.3 -C.sub.6 alkenyl,
• R.sub.3 is selected from naphthyl, tetrahydronaphthyl, indanyl and phenyl having the formula ##STR122## wherein Rc is selected from halogen, C.sub.1 -C.sub.4 linear or branched alkyl, C.sub.3 -C.sub.4 cycloalkyl, C.sub.1 -C.sub.4 alkoxy, hydroxy, cyano and phenyl and x is 0, 1, 2, 3 or 4,
• R.sub.4 is hydroxy or ##STR123## wherein Rb is C.sub.1 -C.sub.6 linear or branched alkyl and
• R.sub.5 and R.sub.6 (i) when separate, are independently selected from hydrogen, C.sub.3 -C.sub.6 cycloalkyl, C.sub.1 -C.sub.6 linear or branched alkyl and monosubstituted C.sub.1 -C.sub.6 linear or branched alkyl wherein the substituent is phenyl, methoxyphenyl or dimethoxyphenyl provided that when one of R.sub.5 and R.sub.6 is said substituted alkyl group the other is hydrogen and (ii) when joined together with the N atom form ##STR124## wherein Z is H or C.sub.1 -C.sub.10 branched or linear alkyl, and pharmaceutically acceptable acid addition and quaternary ammonium salts thereof.