Src family SH2 domain inhibitors

A compound of formula (I):

• wherein:
• Ring a is aryl;
• A is heterocyclyl selected from the group consisting of pyridyl, pyrrolyl, pyrrolinyl, pyrazolyl, piperidinyl, oxopiperidinyl, oxopyrroldinyl and the benzofused derivatives thereof optionally linked to Q or N via an alkoxy, —O—, amino, lower alkyl, lower alkyl amino, carbonyl, amido, amido alkyl, alkoxycarbonyl, carbonylalkyloxy, cycloalkyl or heterocyclyl as defined in this paragraph;
• Q is >C═O;
• B is H;
• R is a bond;
• C is —C(CH3)2—COOH or —NHCOCOOH;
• D is >C═O;
• E is
• R1 is aryl optionally be linked to the adjacent N or C via a lower alkyl,
• R2 and R3 are each independently selected from the group consisting of H or alkyl;
• wherein R2 and R3 are the same or different;
• R4 is alkyl;
• wherein any two substituents R1-R4, when present in adjacent positions on heterocycle E, may be linked together to form a fused 6-membered carbocyclic ring which may be aromatic, partially unsaturated or fully saturated;
• Z is O;
• S;
• NH;
• N-lower alkyl;
• or N-nitrogen-protecting group;
• and the pharmaceutically acceptable tautomers, salts and esters thereof.