The invention relates to quinazoline derivatives of the formula I:- wherein: m is an integer from 1 to 3； R 1 represents halogeno or C 1-3 alkyl； X 1 represents -O-； R 2 is selected from one of the following three groups: 1) C 1-5 alkylR 3 (wherein R 3 is piperidin-4-yl which may bear one or two substituents selected from hydroxy, halogeno, C 1-4 alkyl, C 1-4 hydroxyalkyl and C 1-4 alkoxy； 2) C 2-5 alkenylR 3 (wherein R 3 is as defined hereinbefore)； 3) C 2-5 alkynylR 3 (wherein R 3 is as defined hereinbefore)； and wherein any alkyl, alkenyl or alkynyl group may bear one or more substituents selected from hydroxy, halogeno and amino； and salts thereof； processes for their preparation, pharmaceutical compositions containing a compound of formula I or a pharmaceutically acceptable salt thereof as active ingredient. The compounds of formula I and the pharmaceutically acceptable salts thereof inhibit the effects of VEGF, a property of value in the treatment of a number of disease states including cancer and rheumatoid arthritis.
