Compounds of formula (I) and pharmaceutically acceptable salts thereof are provided: ##STR00001## wherein R.sub.1, m, X, R.sub.2, n, W, p, Y, Z, R.sub.3, R.sub.4, R.sub.5 and q have the meanings as defined in the description. Methods of preparation and uses thereof in therapy, particularly for CNS disorders such as depression or anxiety, are also disclosed.