CYCLOALKYL DERIVATIVES OF 3-HYDROXY-4-PYRIDINONES

The present invention provides an cycloalkyl derivative of 3-hydroxy-4-pyridinone which is useful for the chelation of metal ions such as iron. Its preparation and use is described. In particular, the invention concerns the removal of iron in chemical and biological systems including chelating agents having the formula I wherein R1 is X with the proviso that R2 is Y; or R1 is T with the proviso that R2 is W; or R1 is X with the proviso that R2R5N when taken together form a heterocyclic ring selected from piperidinyl, morpholinyl, pyrrolidinyl or piperazinyl, wherein the group piperidinyl, morpholinyl, pyrrolidinyl or piperazinyl is either unsubstituted or substituted with one to three C1 to C6 alkyl groups. X is C3-C6 cycloalkyl; Y is selected from the group consisting of C1 to C6 cycloalkyl; C1 to C6 alkyl, and C1 to C6 alkyl monosubstituted with a C3-C6 cycloalkyl; T is C1 to C6 alkyl; W is C3-C6 cycloalkyl; R3 is selected from the group consisting of hydrogen and C1 to C6 alkyl; R4 is selected from the group consisting of hydrogen and C1 to C6 alkyl; R5 is selected from the group consisting of hydrogen and C1 to C6 alkyl; and its pharmaceutically acceptable salt thereof. Pharmaceutical compositions of such compounds are useful in the removal of excess body iron from patients with iron overload diseases.