A compound, or pharmaceutically acceptable salt, hydrate or solvate thereof, wherein the compound has the structural formula Id shown below: wherein: R 1 is selected from (1-6C)alkyl, (3-10C)cycloalkyl and heterocyclyl; wherein each of said substituents is optionally substituted by one or more substituent groups independently selected from (1-4C)alkyl, halo, (1-4C)haloalkyl, (1-4C)haloalkoxy, amino, (1-4C)aminoalkyl, cyano, carboxy, carbamoyl, sulphamoyl, mercapto, ureido, NR c R d , C(O)R c , C(O)OR c , OC(O)R c , N(R d )C(O)R c , S(O) y R c where y is 0, 1 or 2, SO 2 N(R d )R c , N(R d )SO 2 R c , Si(R d )(R c )R e and (CH 2 ) z NR d R c where z is 1, 2 or 3; wherein R c , R d and R e are each independently selected from (1-6C)alkyl and (3-6C)cycloalkyl; R 2 is hydrogen; X 4 is CR n , and wherein R n is selected from hydrogen, halo, (1-4C)alkyl and amino; Q 3 is hydrogen, (1-6C)alkyl, (1-6C)alkoxy, aryl, aryl(1-2C)alkyl, (3-8C)cycloalkyl, heteroaryl or heterocyclyl; wherein Q 3 is optionally substituted by one or more substituent groups independently selected from (1-4C)alkyl, halo, amino, cyano, hydroxy, NR t R u , and OR t , wherein R t and R u are each independently selected from hydrogen and (1-4C)alkyl; or Q 3 is optionally substituted by a group of the formula: -L 4 -L Q4 -Z 4 wherein: L 4 is absent or is (1-2C)alkylene; L Q4 is absent or is O; and Z 4 is hydrogen, (1-6C)alkyl, or (3-8C)cycloalkyl; wherein Z 4 is optionally substituted by one or more substituents selected from (1-4C)alkyl, (1-4C)alkoxy, amino, hydroxy, (3-6C)cycloalkyl, NR x R y , and OR x ; wherein R x and R y are each independently selected from hydrogen and (1-4C)alkyl. R 1 is selected from (1-6C)alkyl, (3-10C)cycloalkyl and heterocyclyl; wherein each of said substituents is optionally substituted by one or more substituent groups independently selected from (1-4C)alkyl, halo, (1-4C)haloalkyl, (1-4C)haloalkoxy, amino, (1-4C)aminoalkyl, cyano, carboxy, carbamoyl, sulphamoyl, mercapto, ureido, NR c R d , C(O)R c , C(O)OR c , OC(O)R c , N(R d )C(O)R c , S(O) y R c where y is 0, 1 or 2, SO 2 N(R d )R c , N(R d )SO 2 R c , Si(R d )(R c )R e and (CH 2 ) z NR d R c where z is 1, 2 or 3; wherein R c , R d and R e are each independently selected from (1-6C)alkyl and (3-6C)cycloalkyl; R 2 is hydrogen; X 4 is CR n , and wherein R n is selected from hydrogen, halo, (1-4C)alkyl and amino; Q 3 is hydrogen, (1-6C)alkyl, (1-6C)alkoxy, aryl, aryl(1-2C)alkyl, (3-8C)cycloalkyl, heteroaryl or heterocyclyl; wherein Q 3 is optionally substituted by one or more substituent groups independently selected from (1-4C)alkyl, halo, amino, cyano, hydroxy, NR t R u , and OR t , wherein R t and R u are each independently selected from hydrogen and (1-4C)alkyl; or Q 3 is optionally substituted by a group of the formula: -L 4 -L Q4 -Z 4 wherein: L 4 is absent or is (1-2C)alkylene; L Q4 is absent or is O; and Z 4 is hydrogen, (1-6C)alkyl, or (3-8C)cycloalkyl; wherein Z 4 is optionally substituted by one or more substituents selected from (1-4C)alkyl, (1-4C)alkoxy, amino, hydroxy, (3-6C)cycloalkyl, NR x R y , and OR x ; wherein R x and R y are each independently selected from hydrogen and (1-4C)alkyl. L 4 is absent or is (1-2C)alkylene; L Q4 is absent or is O; and Z 4 is hydrogen, (1-6C)alkyl, or (3-8C)cycloalkyl; wherein Z 4 is optionally substituted by one or more substituents selected from (1-4C)alkyl, (1-4C)alkoxy, amino, hydroxy, (3-6C)cycloalkyl, NR x R y , and OR x ; wherein R x and R y are each independently selected from hydrogen and (1-4C)alkyl. <EOS>