Quinazoline Derivatives as Inhibitors of EGF and/or erbB2 Receptor Tyrosine Kinase

A quinazoline derivative of Formula I:

• wherein:
• R1 is selected from hydrogen, hydroxy, (1-4C)alkoxy and (1-4C)alkoxy(1-4C)alkoxy;
• G1, G2, G3, G4 and G5 are each, independently, selected from hydrogen and halogeno;
• X1 is selected from SO2, CO, SO2N(R7) and C(R7)2, wherein each R7 is, independently, selected from hydrogen and (1-4C)alkyl;
• Q1 is aryl or heteroaryl, which aryl or heteroaryl group optionally bears one or more substituents independently selected from halogeno, cyano and (1-4C)alkoxy;
• R2, R3, R4 and R5 are each, independently, selected from hydrogen and (1-4C)alkyl, or
• R2 and R3 together with the carbon atom to which they are attached form a cyclopropyl ring, or
• R4 and R5 together with the carbon atom to which they are attached form a cyclopropyl ring;
• R6 is selected from hydrogen and (1-4C)alkyl;
• A is selected from hydrogen, Z-(CR8R9)p— and R10;
• p is 1, 2, 3, or 4;
• R8 and R9 are each, independently, selected from hydrogen and (1-4C)alkyl, or an R8 and an R9 group attached to the same carbon atom form a cyclopropyl ring;
• Z is selected from hydrogen, OR11 and NR12R13;
• R11, R12 and R13 are each, independently, selected from hydrogen and (1-4C)alkyl;
• and
• R10 is selected from (1-4C)alkoxy and NR12R13, wherein R12 and R13 are as defined above,
• wherein any CH2 or CH3 group within a Z or an R10 group optionally bears on each said CH2 or CH3 group one or more substituents independently selected from halogeno, (1-4C)alkyl, hydroxy and (1-4C)alkoxy;
• or a pharmaceutically acceptable salt thereof.