A compound of formula:, wherein R 1 is H; R 2 is H; R 3 is hydrogen, methyl, isopropyl or benzyl; and R 4 is H; or R 3 and R 4, together with the atoms to which they are attached, combine to form a five-membered heterocyclic ring; R 5 is an aromatic six membered ring optionally substituted with one or more substituents, wherein the or each substituent is independently a C 1-5 straight or branched alkyl or alkenyl, a halogen, SR 6, SO 2 R 6, OR 6, or NR 6 R 7; m is 0, 1, 2, 3 or 4; n is 0, 1, 2, 3, 4 or 5; the or each X 1 is independently selected from a C 1-5 straight or branched alkyl or alkenyl, a halogen, SR 6, SO 2 R 6, OR 6 or NR 6 R 7; the or each X 2 is independently selected from a C 1-5 straight or branched alkyl or alkenyl, a halogen, SR 6, SO 2 R 6, OR 6 or NR 6 R 7; the or each R 6 is independently selected from the group consisting of: hydrogen, a C 1-5 straight or branched alkyl or alkenyl, C 3-6 cycloalkyl or cycloalkenyl, C 3-6 heterocyclyl or heteroaryl, C 2-4 methane sulphonyl alkyl, C 2-4 dialkylaminoalkyl and the or each R 7 is independently selected from the group consisting of: hydrogen, a C 1-5 straight or branched alkyl or alkenyl, C 3-6 cycloalkyl or cycloalkenyl, C 3-6 heterocyclyl or heteroaryl, C 2-4 methane sulphonyl alkyl, C 2-4 dialkylaminoalkyl and and/or R 6 and R 7 together with the nitrogen atom to which they are attached independently form a 3-7 membered ring which is optionally substituted with one or more substituents, wherein the or each substituent is independently a C 1-5 straight or branched alkyl or alkenyl, a halogen, C R 10, SR 10, SO 2 R 10, OR 10 or NR 10 R 11; the or each R 10 is independently selected from the group consisting of: hydrogen, a C 1-5 straight or branched alkyl or alkenyl, C 3-6 cycloalkyl or cycloalkenyl, C 3-6 heterocyclyl or heteroaryl, C 2-4 methane sulphonyl alkyl, C 2-4 dialkylaminoalkyl and the or each R 11 is independently selected from the group consisting of: hydrogen, a C 1-5 straight or branched alkyl or alkenyl, C 3-6 cycloalkyl or cycloalkenyl, C 3-6 heterocyclyl or heteroaryl, C 2-4 methane sulphonyl alkyl, C 2-4 dialkylaminoalkyl and pis 1, 2, 3, 4 or 5; and R 8 and R 9 together with the nitrogen atom to which they are attached independently form a 3-7 membered ring; or a pharmaceutically acceptable salt, solvate, tautomeric form or polymorphic form thereof, where the following compound is disclaimed, wherein R 1 is H; R 2 is H; R 3 is hydrogen, methyl, isopropyl or benzyl; and R 4 is H; or R 3 and R 4, together with the atoms to which they are attached, combine to form a five-membered heterocyclic ring; R 5 is an aromatic six membered ring optionally substituted with one or more substituents, wherein the or each substituent is independently a C 1-5 straight or branched alkyl or alkenyl, a halogen, SR 6, SO 2 R 6, OR 6, or NR 6 R 7; m is 0, 1, 2, 3 or 4; n is 0, 1, 2, 3, 4 or 5; the or each X 1 is independently selected from a C 1-5 straight or branched alkyl or alkenyl, a halogen, SR 6, SO 2 R 6, OR 6 or NR 6 R 7; the or each X 2 is independently selected from a C 1-5 straight or branched alkyl or alkenyl, a halogen, SR 6, SO 2 R 6, OR 6 or NR 6 R 7; the or each R 6 is independently selected from the group consisting of: hydrogen, a C 1-5 straight or branched alkyl or alkenyl, C 3-6 cycloalkyl or cycloalkenyl, C 3-6 heterocyclyl or heteroaryl, C 2-4 methane sulphonyl alkyl, C 2-4 dialkylaminoalkyl and the or each R 7 is independently selected from the group consisting of: hydrogen, a C 1-5 straight or branched alkyl or alkenyl, C 3-6 cycloalkyl or cycloalkenyl, C 3-6 heterocyclyl or heteroaryl, C 2-4 methane sulphonyl alkyl, C 2-4 dialkylaminoalkyl and and/or R 6 and R 7 together with the nitrogen atom to which they are attached independently form a 3-7 membered ring which is optionally substituted with one or more substituents, wherein the or each substituent is independently a C 1-5 straight or branched alkyl or alkenyl, a halogen, C R 10, SR 10, SO 2 R 10, OR 10 or NR 10 R 11; the or each R 10 is independently selected from the group consisting of: hydrogen, a C 1-5 straight or branched alkyl or alkenyl, C 3-6 cycloalkyl or cycloalkenyl, C 3-6 heterocyclyl or heteroaryl, C 2-4 methane sulphonyl alkyl, C 2-4 dialkylaminoalkyl and the or each R 11 is independently selected from the group consisting of: hydrogen, a C 1-5 straight or branched alkyl or alkenyl, C 3-6 cycloalkyl or cycloalkenyl, C 3-6 heterocyclyl or heteroaryl, C 2-4 methane sulphonyl alkyl, C 2-4 dialkylaminoalkyl and pis 1, 2, 3, 4 or 5; and R 8 and R 9 together with the nitrogen atom to which they are attached independently form a 3-7 membered ring;