Condensed tricyclic compounds as protein kinase inhibitors

A compound of formula I,

• wherein:
• R1 and R2 each independently represents hydrogen, C1-12 alkyl, C3-12 cycloalkyl or heterocycloalkyl (which latter three groups are optionally substituted by one or more substituents selected from ═O and Q1), provided that at least one of R1 and R2 is not hydrogen;
• or
• R1 and R2 may be linked together along with the carbon atom to which they are both attached to form a 3- to 12-membered ring, optionally containing one or more heteroatoms selected from oxygen, nitrogen and sulfur, optionally containing one or more unsaturations, and which ring is optionally substituted by one or more substituents selected from ═O, ═S, ═N(R20) and E1;
• R3 represents hydrogen, halo, —CN, C1-12 alkyl (optionally substituted by one or more Q2 groups), C3-12 cycloalkyl, heterocycloalkyl (which latter two groups are optionally substituted by one or more substituents selected from ═O and Q3), aryl or heteroaryl (which latter two groups are optionally substituted by one or more Q4 groups);
• R4 represents —N(R40)R41 or —OR42;
• R5 represents hydrogen, C1-12 alkyl, —C(O)—C1-12 alkyl or —C(O)O—C1-12 alkyl, which latter three groups are optionally substituted by one or more Q5 groups;
• R6 represents hydrogen, halo, —CN, —N(R60)R61, C1-12 alkyl, C3-12 cycloalkyl, heterocycloalkyl (which latter three groups are optionally substituted by one or more substituents selected from ═O and Q6), aryl or heteroaryl (which latter two groups are optionally substituted by one or more Q7 groups);
• R7a and R7b each independently represents hydrogen, halo, —N(R70)R71 or —C(O)N(R72)R73;
• each R20, R40, R41, R42, R60 and R61 independently represents hydrogen, C1-6 alkyl, C3-6 cycloalkyl, heterocycloalkyl (which latter three groups are optionally substituted by one or more substituents selected from E2 and ═O), aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from E3);
• or
• any relevant pair of R40, R41, R60 and R61, when attached to the same nitrogen atom, may be linked together along with the nitrogen atom to which they are attached to form a 4- to 12-membered ring, optionally containing one or more heteroatoms selected from oxygen, nitrogen and sulfur in addition to the requisite nitrogen atom, optionally containing one or more unsaturations, and which ring is optionally substituted by one or more substituents selected from E4;
• each R70, R71, R72 and R73 independently represents, hydrogen or C1-3 alkyl optionally substituted by one or more halo atoms;
• each Q1, Q2, Q3, Q4, Q5, Q6 and Q7 independently represents halo, —CN, —N(R80)R81, —OR80, —C(═Y)—R80, —C(═Y)—OR80, —C(═Y)N(R80)R81, —OC(═Y)—R80, —OC(═Y)—OR80, —OC(═Y)N(R80)R81, —OS(O)2OR80, —P(═Y)(OR80)(OR81), —OP(OR80)(OR81), —N(R82)C(═Y)R81, —N(R82)C(═Y)OR81, —N(R82)C(═Y)N(R80)R81, —NR82S(O)2R8, —NR82S(O)2N(R80)R81, —S(O)2N(R80)R81, —SC(═Y)R80, —SC(═Y)OR80, —SC(═Y)N(R80)R81, —S(O)2R80, —SR80, —S(O)R80, —S(O)2OR80, C1-12 alkyl, C3-12 cycloalkyl, heterocycloalkyl (which latter three groups are optionally substituted by one or more substituents selected from ═O and E5), aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from E6);
• each E1, E2, E3, E4, E5 and E6 independently represents:
• (i) Q8;
• (ii) C1-6 alkyl, C3-6 cycloalkyl or heterocycloalkyl, each of which is optionally substituted by one or more substituents selected from ═O and Q9;
• or
• (iii) aryl or heteroaryl, both of which are optionally substituted by one or more Q10 groups;
• each Q8, Q9 and Q10 independently represents
• halo, —CN, —N(R83)R84, —OR83, —C(═Ya)—R3, —C(═Ya)—OR83, —C(═Ya)N(R83)R84, —N(R85)C(═Ya)R84, —NR85S(O)2R83, —S(O)2R83, —SR83, —S(O)R83, C1-6 alkyl or aryl, wherein the latter two groups are optionally substituted by one or more fluoro atoms;
• each Y and Ya independently represents [═]O or [═]S;
• each R80, R81, R82, R83, R84 and R85 independently represents hydrogen or C1-6 alkyl optionally substituted by one or more substituents selected from fluoro, —OR90 and —N(R91)R92;
• R90, R91 and R92 independently represent hydrogen or C1-6 alkyl optionally substituted by one or more fluoro atoms;
• or a pharmaceutically acceptable ester, amide, solvate or salt thereof.