The present invention relates to new compounds of formula (I), wherein P, Q, X.sup.1, X.sup.2, X.sup.3, X.sup.4, X.sup.5, X.sup.6, R.sup.1, R.sup.2, R.sup.3, m, n, and p are as defined as in formula (I), or salts, or hydrates thereof, processes for their preparation and new intermediates used in the preparation thereof, pharmaceutical compositions containing said compounds and to the use of said compounds in therapy.