Zileuton is an orally active inhibitor
of 5-lipoxygenase, the enzyme that catalyzes the formation
of leukotrienes from arachidonic acid. Zileuton has the chemical
Zileuton has the molecular formula
and a molecular weight
of 236.29. It is a racemic
mixture (50:50) of R(+)
and S(-) enantiomers. Zileuton is a practically odorless, white,
crystalline powder that is soluble
in methanol and ethanol,
slightly soluble in
acetonitrile, and practically insoluble
in water and hexane. The
melting point ranges from
144.2oC to 145.2oC.
ZYFLO tablets for oral
is supplied in one dosage
strength containing 600mg of zileuton.
Inactive Ingredients: crospovidone, hydroxypropyl cellulose,
hydroxypropyl methylcellulose, magnesium
cellulose, pregelatinized starch,
propylene glycol, sodium
starch glycolate, talc,
and titanium dioxide.