N-carbamoyl analogs of zafirlukast: Potent receptor antagonists of leukotriene D4

Abstract Exploration of the indole nitrogen region of Zafirlukast ( 1 ) has uncovered a potent series of cysteinyl leukotriene D 4 (LTD 4 ) antagonists. These studies showed that a variety of functionality could be incorporated in this region of the molecule without sacrificing potency. Efforts to exploit this site in order to improve oral efficacy are discussed.