This invention relates to the use of compounds of Formula (I) as vascular damaging agents: wherein X is selected from: --O--, --S--, --S(O)--, --S(O.sub.2)--, --N(R.sub.5)--, --C(O)--, --C(O)N(R.sub.5)--, --N(R.sub.5)C(O)--, --S(O2)N(R.sub.5)--, or --N(R.sub.5)S(O.sub.2)--; R.sub.1 is independently selected from: amino, halo, hydroxy, --OPO.sub.3H.sub.2, C.sub.1-4alkyl, or C.sub.1-4alkoxy, wherein the amino group is optionally substituted by an amino acid residue and the hydroxy group is optionally esterified; R.sub.2 is selected from: hydrogen or C.sub.1-4alkyl; R.sub.3 is selected from: hydrogen, halo, hydroxy, hydroxyC.sub.1-4alkyl, cyano, cyanoC.sub.1-4alkyl, carboxy, carboxyC.sub.1-4alkyl, C.sub.1-4alkanoyl, C.sub.1-4alkanoylC.sub.1-4alkyl, carbamoyl, carbamoylC.sub.1-4alkyl, C.sub.1-4alkoxy, C.sub.1-4alkoxycarbonyl, C.sub.1-4alkoxycarbonylC.sub.1-4alkyl, C.sub.1-4alkoxycarbonylamino, amino, N--C.sub.1-4alkylamino, NN-diC.sub.1-4alkylamino, aminoC.sub.1-4alkyl, N--C.sub.1-4alkylaminoC.sub.1-4alkyl, NN-diC.sub.1-4alkylaminoC.sub.1-4alkyl, ureido, or C.sub.1-4alkylureyleno; R.sub.4 is independently selected from: C.sub.1-4alkyl, C.sub.1-4alkoxy or halo; R.sub.5 is selected from: hydrogen or C.sub.1-4alkyl; n is 0 or 1; p is 0, 1, 2 or 3; and q is 0, 1 or 2; or a salt, pro-drug or solvate thereof. The invention also relates to novel compounds of Formula (I) and to processes for the preparation of compounds of Formula (I). ##STR00001##