Zafirlukast (ICI-204219)

InformationZafirlukast (ICI-204219) Zafirlukast (ICI-204219) is an oral leukotriene receptor antagonist (LTRA), used to prevent asthma symptoms.In vitroZafirlukast is similar to 3-methylindole because it contains an N-methylindole moiety that has a 3-alkyl substituent on the indole ring. Zafirlukast readily forms (10% conversion in 60 min) a GSH adduct with molecular mass of 880 Da upon incubation with horseradish peroxidase. Zafirlukast produces time-, concentration-, and NADP(H)-dependent inactivation of CYP3A4. Zafirlukast is shown to inhibit CYP3A enzyme activity in vitro (nonpreincubation inhibition) with a Ki of 2 μM in one report, but higher values have been published, and our KI for the inactivation process is 13.4 μM. Zafirlukast has high plasma protein binding (>99%), which would lower the free-drug concentration. Zafirlukast undergoes two successive one-electron oxidations to afford a highly electrophilic α,β-unsaturated iminium species, which reacts spontaneously with GSH to yield the observed adduct.In vivoZafirlukast is a potent and selective cysteinyl leukotriene receptor antagonist which is used mainly in the prophylaxis of bronchial asthma. Zafirlukast in a dose of 80 mg/kg orally produces a significant decrease in tissue malondialdehyde, myeloperoxidase, and an increase in both reduced glutathione and catalase levels, while there is no significant changes with the rectal route.Cell Datacell lines：PBMC effector cellsConcentrations：Incubation Time：Powder Purity:≥99%. Specification: 10mM in DMSO Molecular Formula: C31H33N3O6S Molecular Weight: 575.68