##STR00001## wherein R represents a halogen atom or a C.sub.1-4 alkyl group; R.sub.1 represents a C.sub.1-4 alkyl group; R.sub.2 represents hydrogen or a C.sub.1-4 alkyl group; R.sub.3 represents hydrogen, or a C.sub.1-4 alkyl group; R.sub.4 represents a trifluoromethyl group; R.sub.5 represents hydrogen, a C.sub.1-4 alkyl group or C(O)R.sub.6; R.sub.6 represents C.sub.1-4 alkyl, C.sub.3-7 cycloalkyl, NH(C.sub.1-4 alkyl) or N(C.sub.1-4alkyl).sub.2; m is zero or an integer from 1 to 3; n is an integer from 1 to 3 and pharmaceutically acceptable salts and solvates thereof; to processes for their preparation and their use in the treatment of conditions mediated by tachykinins.