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
##STR00001##
wherein R.sup.1 is X with the proviso that R.sup.2 is Y; or R.sup.1 is T
with the proviso that R.sup.2 is W; or R.sup.1 is X with the proviso that
R.sup.2R.sup.5N 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 C.sub.1 to C.sub.6 alkyl
groups. X is C.sub.3-C.sub.6 cycloalkyl; Y is selected from the group
consisting of C.sub.1 to C.sub.6 cycloalkyl; C.sub.1 to C.sub.6 alkyl,
and C.sub.1 to C.sub.6 alkyl monosubstituted with a C.sub.3-C.sub.6
cycloalkyl; T is C.sub.1 to C.sub.6 alkyl; W is C.sub.3-C.sub.6
cycloalkyl; R.sup.3 is selected from the group consisting of hydrogen and
C.sub.1 to C.sub.6 alkyl; R.sup.4 is selected from the group consisting
of hydrogen and C.sub.1 to C.sub.6 alkyl; R.sup.5 is selected from the
group consisting of hydrogen and C.sub.1 to C.sub.6 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.