Imidazolyl-cyclic acetals

A compound of formula (I):

• wherein:
• R1 is optionally substituted 4-pyrimidinyl;
• R2 is optionally substituted aryl or optionally substituted heteroaryl;
• R3 represents a group —L1—R7 or —L2—R8
• where L1 represents a straight- or branched-chain alkylene linkage consisting of 1 to 6 carbon atoms optionally substituted by halogen or oxo;
• R7 is hydrogen, aryl, cyano, cycloalkyl, heteroaryl, heterocycloalkyl, nitro, —S(O)nR9, (where R9 is alkyl, aryl, arylalkyl, cycloalkyl, heteroaryl, heteroarylalkyl, or heterocycloalkyl and n is zero or an integer 1 or 2), —NHSO2R9, —C(═Z)OR10 (where Z is an oxygen or sulphur atom and R10 is hydrogen or R9), —C(═Z)R10, —OR10—N(R11)—C(═Z)R9 (where R11 is hydrogen or alkyl), —NY1Y2 {where Y1 and Y2 are independently hydrogen, alkenyl, alkyl, alkynyl, aryl, arylalkyl, cycloalkenyl, cycloalkyl, heteroaryl or heteroarylalkyl, or the group —NY1Y2 may form a 5-7 membered cyclic amine which may optionally contain a further heteroatom selected from O, S, or NY3 (where Y3 is hydrogen, alkyl, aryl, arylalkyl, —CHO, —C(═Z)R9 or —SO2R9), or which may also be fused to additional aryl, heteroaryl, heterocycloalkyl or cycloalkyl rings to form a bicyclic or tricyclic ring system}, —SO2—NY1Y2, —C(═Z)—NY1Y2, —N(R11)—C(═Z)—NY1Y2, —N(OR10)—C(═Z)—NY1Y2, —N(OR10)—C(═Z)R10, —C(═NOR10)R10, —C(═Z)NR10OR12 (where R12 is hydrogen, alkyl, aryl or arylalkyl), —N(R11)—C(═NR13)—NY1Y2 (where R13 is hydrogen, cyano, alkyl, cycloalkyl or aryl), or —N(R11)—C(═Z)OR11;
• L2 represents a direct bond or a straight- or branched-carbon chain consisting of 2 to 6 carbon atoms and containing a double or triple carbon-carbon bond;
• and R8 is hydrogen, aryl, cycloalkenyl, cycloalkyl, heteroaryl or heterocycloalkyl;
• R4 represents a group —L3—R14
• where L3 represents a direct bond or a straight- or branched-chain alkylene linkage consisting of 1 to 6 carbon atoms (optionally substituted by halogen, hydroxy, alkoxy or oxo);
• and
• R14 is hydrogen, alkyl, azido, hydroxy, alkoxy, aryl, arylalkyloxy, aryloxy, carboxy (or an acid bioisostere), cycloalkyloxy, heteroaryl, heteroarylalkyloxy, heteroaryloxy, heterocycloalkyl, heterocycloalkyloxy, nitro, —NY4Y5, {where Y4 and Y5 are independently hydrogen, aryl, cycloalkyl, heterocycloalkyl, heteroaryl or alkyl optionally substituted by alkoxy, aryl, cyano, cycloalkyl, heteroaryl, heterocycloalkyl, hydroxy, oxo, —CO2R10, —CONY1Y2 or —NY1Y2, or the group —NY4Y5 may form a 5-7 membered cyclic amine which (i) may be optionally substituted with one or more substituents selected from alkoxy, carboxamido, carboxy, hydroxy, oxo (or a 5, 6,or 7 membered cyclic acetal derivative thereof), R9 or alkyl substituted by carboxy, carboxamido or hydroxy (ii) may also contain a further heteroatom selected from O, S, SO2 or NY6 (where Y6 is hydrogen, alkyl, aryl, arylalkyl, —C(═Z)R9, —C(═Z)OR9 or —SO2R9) and (iii) may also be fused to additional aryl, heteroaryl, heterocycloalkyl or cycloalkyl rings to form a bicyclic or tricyclic ring system}, —N(R10)—C(═Z)—R15 (where R15 is alkyl, alkoxy, aryl, arylalkyloxy, cycloalkyl, heteroaryl, heteroarylalkoxy or heterocycloalkyl);
• —N(R10)—C(═Z)—L4—R16 (where R16 is alkoxy, aryl, arylalkyloxy, arylalkyloxycarbonylamino, carboxy (or an acid bioisostere), cycloalkyl, cyano, halo, heteroaryl, heteroarylalkoxy, heterocycloalkyl, hydroxy or —NY1Y2, and L4 is a straight- or branched-chain alkylene linkage consisting of 1 to 6 carbon atoms), —NH—C(═Z)—NH—R15, —NH—C(═Z)—NH—L4—R16, —N(R10)—SO2—R15, —N(R10)—SO2—L4—R16, —S(O)nR9, —C(═Z)—NY4Y5 or —C(═Z)—OR9;
• R5 represents hydrogen, alkyl or hydroxyalkyl;
• or
• R4 and R5, when attached to the same carbon atom, may form with the said carbon atom a cycloalkyl, cycloalkenyl or heterocycloalkyl ring or a group C═CH2;
• R6 represents hydrogen or alkyl;
• and
• m is zero or an integer 1 or 2;
• or N-oxides thereof;
• or pharmaceutically acceptable salts or solvates thereof.