Inhibitor compounds

A compound of formula Ic shown below:

• wherein:
• R1 is selected from heteroaryl, and NR7R8
• and wherein R1 is optionally substituted by one or more substituent groups selected from fluoro, chloro, trifluoromethyl, trifluoromethoxy, cyano, nitro, hydroxy, amino, carboxy, carbamoyl, sulphamoyl, (1-4C)alkyl, (1-4C)alkoxy, S(O)qCH3 (where q is 0, 1, or 2), methylamino, dimethylamino, aryl, aryl(1-2C)alkyl, heteroaryl, heteroaryl(1-2C)alkyl, heterocyclyl, heterocyclyl(1-2C)alkyl, (3-8C)cycloalkyl, or (3-8C)cycloalkyl(1-2C)alkyl, and wherein any (1-4C)alkyl, (1-4C)alkoxy, aryl, heteroaryl, heterocyclyl, or (3-8C)cycloalkyl moiety present within a substituent group on R1 is optionally further substituted by fluoro, chloro, trifluoromethyl, trifluoromethoxy, cyano, nitro, hydroxy, amino, carboxy, carbamoyl, sulphamoyl, (1-4C)alkyl, NRaRb, ORa, C(O)Ra, C(O)ORa, OC(O)Ra, N(Rb)ORa, C(O)N(Rb)Ra, N(Rb)C(O)Ra, S(O)pRa (where p is 0, 1, or 2), SO2N(Rb)Ra, or N(Rb)SO2Ra, wherein Ra and Rb are each independently selected from H or (1-4C)alkyl;
• R3 is hydrogen, (1-4C)alkyl, or (3-6C)cycloalkyl
• R4 is hydrogen;
• Ar has the formula:
• wherein all of A1, A2, and A3 are CH;
• R5 is (1-3C)alkoxy, or (1-3C)fluoroalkoxy;
• R6 is selected from heteroaryl and heterocyclyl,
• and wherein R6 is optionally further substituted by one or more substituent groups independently selected from oxo, halo, cyano, nitro, hydroxy, NR22R23, (1-4C)alkoxy, (1-4C)alkyl, (3-8C)cycloalkyl, (3-8C)cycloalkyl-(1-3C)alkyl, (1-5C)alkanoyl, (1-5C)alkylsulphonyl, heterocyclyl, heterocyclyl-(1-2C)alkyl, heteroaryl, heteroaryl-(1-2C)alkyl, CONR22R23, and SO2NR22R23;
• wherein R22 and R23 are each independently selected from hydrogen, (1-4C)alkyl, (3-6C)cycloalkyl, or (3-6C)cycloalkyl(1-2C)alkyl;
• and wherein when said substituent group comprises an alkyl, cycloalkyl, heterocyclyl, or heteroaryl moiety then said moiety is optionally further substituted by hydroxy, fluoro, chloro, cyano, CF3, OCF3, (1-2C)alkyl, (1-2C)alkoxy, SO2(1-2C)alkyl, or NReRf (where Re and Rf are each independently selected from hydrogen, (1-3C)alkyl, (3-6C)cycloalkyl, or (3-6C)cycloalkyl(1-2C)alkyl);
• R8 is selected from hydrogen, (1-6C)alkyl, (1-6C)alkoxy, (3-9C)cycloalkyl, (3-9C)cycloalkyl-(1-2C)alkyl, aryl, aryl-(1-2C)alkyl, heterocyclyl, heterocyclyl-(1-2C)alkyl, heteroaryl, or heteroaryl-(1-2C)alkyl, and wherein R8 is optionally further substituted by one or more substituents selected from hydroxy, fluoro, chloro, cyano, CF3, OCF3 (1-2C)alkyl, or (1-2C)alkoxy;
• and
• R7 is selected from hydrogen, (1-6C)alkyl, (3-6C)cycloalkyl, or (3-6C)cycloalkyl-(1-2C)alkyl, and wherein R7 is optionally further substituted by one or more substituents selected from hydroxy, fluoro, chloro, cyano, CF3, OCF3, (1-2C)alkyl, or (1-2C)alkoxy;
• or a pharmaceutically acceptable salt or solvate thereof.