Selective anti-cancer compounds

A compound of formula I,

• wherein,
• Z represents N or CR4;
• L represents C(R6a)═C(R6b);
• X1 to X5 are independently N or CR8, provided that at least one of X1 and X2 is N;
• X6 and X7 are independently N or CR9;
• Y represents N or CR10;
• R1 represents H, —C(O)R11a or —C(S)R11b;
• R2 to R4, R8 and R10, at each occurrence, independently represents:
• (a) H;
• (b) halo;
• (c) CN;
• (d) C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are unsubstituted or substituted by one or more substituents selected from halo, nitro, CN, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are unsubstituted or substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), Cy1 (which Cy1 group is unsubstituted or is substituted by one or more substituents selected from halo, nitro, CN, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are optionally substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), OR12a, S(O)qR12b, S(O)2NR12cR12d, NR12eS(O)2R12f, NR12gR12h, aryl and Het1);
• (e) Cy2 (which Cy2 group is unsubstituted or is substituted by one or more substituents selected from halo, nitro, CN, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are optionally substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), OR13a, S(O)qR13b, S(O)2NR13cR13d, NR13eS(O)2R13f, NR13gR13h, aryl and Het2),
• (f) Heta (which Heta group is unsubstituted or substituted by one or more substituents selected from halo, nitro, CN, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are optionally substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), OR14a, S(O)qR14b, S(O)2NR14cR14d, NR14eS(O)2R14f, NR14gR14h, aryl and Het3);
• (g) OR15a;
• (h) S(O)qR15b;
• (i) S(O)2NR15cR15d;
• (j) NR15eS(O)2R15f;
• (k) NR15gR15h,
• where R3, R4 and each R8, when present, may also, in addition, independently represent nitro;
• R5 and R9, at each occurrence, independently represent H, halo, CN, nitro, C1-4 alkyl (which latter group is unsubstituted or substituted by one or more substituents selected from halo, nitro, CN, OR16a and NR16gR16h), OR17s, S(O)q(O)R17b, S(O)2NR17cR17d, NR17eS(O)2R17f or NR17gR17h;
• R6a represents H, CN or —C(O)NR18aR18b;
• R6b, independently at each occurrence, represents H, CN or C1-4 alkyl, which latter group is unsubstituted or substituted with halo or OR19;
• R7a and R7b represent H or C1-4 alkyl, which latter group is unsubstituted or substituted with halo or OR20;
• R11a and R11b, when present, represent,
• (a) H;
• (b) C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are unsubstituted or substituted by one or more substituents selected from halo, nitro, ═O, CN, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are unsubstituted or substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), OR21a, S(O)qR21b, S(O)2NR21cR21d, NR21eS(O)2R21f, NR21gR21h, aryl, Cy3 (which Cy3 group is unsubstituted or is substituted by one or more substituents selected from halo, nitro, CN, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are optionally substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), OR22a, S(O)qR22b, S(O)2NR22cR22d, NR22eS(O)2R22f, NR22gR22h, aryl and Het4) and Het5);
• (c) C3-10 cycloalkyl, C4-10 cycloalkenyl (which latter two groups are optionally substituted by one or more substituents selected from halo, OH, ═O, C1-6 alkyl and C1-6 alkoxy);
• (d) Hetb (which Hetb group is unsubstituted or substituted by one or more substituents selected from halo, nitro, CN, C(O)OC1-4 alkyl, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are optionally substituted by one or more substituents selected from Het8, OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), OR23a, S(O)qR23b, S(O)2NR23cR23d, NR23eS(O)2R23f, NR23gR23h, aryl and Het6),
• (e) OR24a;
• (f) NR24bS(O)2R24c;
• (g) NR24dR24e;
• R12a to R12h, R13a to R13h, R14a to R14h, R15a to R15h, R16a to R16h, R17a to R17h, R18a, R18b, R19, R20, R21a to R21h, R22a to R22h, R23a to R23h and R24a to R24e independently represent, at each occurrence, H, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are optionally substituted by one or more substituents selected from halo, nitro, ═O, C(O)OC1-4 alkyl, CN, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C3-6 cycloalkyl (which latter three groups are optionally substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), OR25a, S(O)qR25b, S(O)2NR25cR25d, NR25eS(O)2R25f, NR25gR25h, aryl and Het7), C3-10 cycloalkyl, or C4-10 cycloalkenyl (which latter two groups are optionally substituted by one or more substituents selected from halo, OH, ═O, C1-6 alkyl and C1-6 alkoxy) or Hetc, or
• R12-17c and R12-17d, R12-17g and R12-17h, R21-23c and R21-23d, R21-23g and R21-23h, R24b and R24c, and R24d and R24e may represent, together with the nitrogen atom to which they are attached, a 3- to 10-membered heterocyclic ring that may be aromatic, fully saturated or partially unsaturated and which may additionally contain one or more heteroatoms selected from O, S and N, which heterocyclic ring is optionally substituted by one or more substituents selected from halo, nitro, CN, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl (which latter three groups are optionally substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy);
• Het1 to Het8 and Heta to Hetc independently represent a 4- to 14-membered heterocyclic groups containing one or more heteroatoms selected from O, S and N, which heterocyclic groups may comprise one, two or three rings and may be substituted by one or more substituents selected from ═O, halo, C1-6 alkyl, which latter group is optionally substituted by one or more substituents selected from halo, —OR26a, —NR26bR26c, —C(O)OR26d and —C(O)NR26eR26f;
• Cy1 to Cy3, at each occurrence, independently represents a 3- to 10-membered aromatic, fully saturated or partially unsaturated carbocyclic ring;
• R25a to R25h and R26a to R26f independently represent at each occurrence, H, C1-4 alkyl, C2-4 alkenyl, C2-4 alkynyl which latter three groups are optionally substituted by one or more substituents selected from halo, nitro, CN, C1-4 alkyl, C2-4 alkenyl, C2-4 alkynyl (which latter three groups are optionally substituted by one or more substituents selected from OH, ═O, halo, C1-4 alkyl and C1-4 alkoxy), C3-6 cycloalkyl, or C4-6 cycloalkenyl (which latter two groups are optionally substituted by one or more substituents selected from halo, OH, ═O, C1-4 alkyl and C1-4 alkoxy),
• q represents 0, 1 or 2, or
• a pharmaceutically acceptable salt or solvate thereof.