Phosphorous derivatives as kinase inhibitors

A compound of the formula VIa:

• wherein
• X1 is NRb1 or CRb;
• X3 is NRd1 or CRd;
• X4 is NRe1 or CRe;
• Ring A and Ring E are each an independently selected aryl or heteroaryl ring, the heteroaryl ring being a 5- or 6-membered ring containing 1 to 4 heteroatoms selected from N, O and S(O)r;
• each occurrence of Ra, Rb, Rd, Re, and Rg is independently selected from the group consisting of halo, —CN, —NO2, —R1, —OR2, —O—NR1R2, —NR1R2, —NR1—NR1R2, —NR1—OR2, —C(O)YR2, —OC(O)YR2, —NR1C(O)YR2, —SC(O)YR2, —NR1C(═S)YR2, —OC(═S)YR2, —C(═S)YR2, —YC(═NR1)YR2, —YC(═N—OR1)YR2, —YC(═N—NR1R2)YR2, —YP(═O)(YR3)(YR3), —Si(R3a)3, —NR1SO2R2, —S(O)rR2, —SO2NR1R2 and —NR1SO2NR1R2;
• or alternatively, each Ra and Rg may also be an independently selected moiety, —P(═O)(R3)2 or a ring system containing the moiety —P(═O)(R3)— as a ring member;
• Rb1, Rd1 and Re1 are absent;
• or alternatively two adjacent substituents selected from Rd, Rd1, Re, and Re1, or two adjacent Ra moieties, can form, with the atoms to which they are attached, a fused, 5-, 6- or 7-membered saturated, partially saturated or unsaturated ring, which contains 0-4 heteroatoms selected from N, O and S(O), and which may bear up to four substituents;
• at least one of Ra and Rg is or contains a moiety, —P(═O)(R3)2 or a ring system containing the moiety —P(═O)(R3)—as a ring member;
• L is 0 or NH;
• r is 0, 1 or 2;
• s is 1, 2, 3, 4 or 5;
• p is 1, 2, 3 or 4;
• each occurrence of Y is independently a bond, —O—, —S— or —NR′—;
• each occurrence of R1 and R2 is independently H or an alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroalkyl, heterocyclic or heteroaryl moiety;
• each occurrence of R3 is independently an alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroalkyl, heterocyclic or heteroaryl moiety, or two adjacent R3 moieties combine to form a ring system including a phosphorous atom;
• each occurrence of R3a is independently selected from alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroalkyl, heterocyclic, and heteroaryl;
• alternatively, each NR1R2 moiety may be a 5-, 6- or 7-membered saturated, partially saturated or unsaturated ring, which can be optionally substituted and which contains 0-2 additional heteroatoms selected from N, O and S(O)r;
• and
• each of the foregoing alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl and heterocyclic moieties is optionally substituted.