Substituted quinazolines

A compound of Formula (I) or a pharmaceutically acceptable salt or solvate thereof

• wherein:
• R1, R2, R3 and R4 independently represent hydrogen or a blocking group which functions to prevent metabolic reaction either directly or indirectly at the 3-position;
• or R1 and R2, and/or R3 and R4 together with the carbon to which they are attached form a blocking group which functions to prevent metabolic reaction at the 3-position, the remainder of groups R1 to R4 being hydrogen;
• R5 is selected from the group comprising:
• fluoro, chloro, bromo and iodo;
• R6 is selected from the group comprising:
• fluoro, chloro, bromo and iodo;
• and
• R7 and R8 are independently selected from the group comprising:
• H;
• halo;
• cyano;
• C1-6 alkyl, C1-6 haloalkyl, C1-6 alkoxy, and C1-6 haloalkoxy;
• and
• R9 is H or C1-6 alkyl,
• R10 is selected from the group comprising:
• hydrogen;
• C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl and C3-8 cycloalkyl wherein each of the foregoing groups may be optionally substituted by 1 to 5 groups chosen independently from the group comprising:
• halo, hydroxyl, cyano, nitro, C1-4 alkylsulphonyl and COOH;
• or R10 is a pharmaceutically acceptable cation, and
• X is O or S,
• provided always that R1, R2, R3 and R4 are not all hydrogen.