Indolinone derivatives

A compound of formula (I)

• wherein:
• (i) R1 represents a hydrogen atom or a (1-4C)alkyl group;
• and R2 represents a group of formula -A1-NR5R6 in which each of R5 and R6 independently represents a hydrogen atom or a (1-4C)alkyl group and A1 represents (CH2)m, (CH2)n-A2-(CH2)p or (CH2CH2O)qCH2CH2 in which m is an integer of from 2 to 10, each of n and p is an integer of from 1 to 6, A2 is CH═CH, phenylene, biphenylene, cyclohexylene or piperazinylene and q is 1, 2 or 3;
• (ii) R1 and R2 together represent -A3-NR7-A4- in which each of A3 and A4 independently represents (CH2)r or (CH2CH2O)sCH2CH2 in which r is an integer of from 2 to 6, s is 1, 2 or 3, and R7 represents a hydrogen atom or a (1-4C)alkyl group;
• (iii) R1 and R2 together with the nitrogen atom to which they are attached represent a piperidinyl group, which piperidinyl group bears a substituent of formula -A5-R8 at the 4 position, in which A5 represents (1-4C)alkylene and R8 represents piperidin-4-yl;
• or
• (iv) R1 and R2 together with the nitrogen atom to which they are attached represent a pyrrolidinyl, piperidinyl or morpholino group;
• and
• R3 and R4 each independently represents a hydrogen atom, a halogen atom, a (1-4C)alkyl group, a (1-4C)alkoxy group, a phenyl group which is unsubstituted or substituted by one or two substituents selected independently from a halogen atom, a (1-4C)alkyl group and a (1-4C)alkoxy group, a group of formula R8S(O)2NR9—, a group of formula R10N(R11)S(O)2—, a group of formula R12C(O)N(R13)— or a group of formula R14N(R15)C(O)— in which each of R8, R10, R12 and R14 independently represents a (1-4C)alkyl group or a phenyl group which is unsubstituted or substituted by one or two substituents selected independently from a halogen atom, a (1-4C)alkyl group and a (1-4C)alkoxy group, and each of R9, R11, R13 and R15 independently represents a hydrogen atom or a (1-4C)alkyl group;
• or a pharmaceutically-acceptable salt thereof.