Synthesis, Structure-Activity Relationships, and Pharmacological Evaluation of a Series of Fluorinated 3-Benzyl-5-Indolecarboxamides: Identification of 4-[[5-[((2R)-2-Methyl-4,4,4-trifluorobutyl)carbamoyl]-1-methylindol-3-yl]methyl]-3methoxy-N-[(2-methylphenyl)sulfonyl]benzamide, a Potent, Orally Active Antagonist of Leukotrienes D4 and E4
作者:Robert T. Jacobs、Peter R. Bernstein、Laura A. Cronk、Edward P. Vacek、Lisa F. Newcomb、David Aharony、Carl K. Buckner、Edward J. Kusner
DOI:10.1021/jm00035a008
日期:1994.4
The continued exploration of a series of 3-(arylmethyl)-1H-indole-5-carboxamides by the introduction of fluorinated amide substituents has resulted in the discovery of 4-[[5-[((2R)-2-methyl-4,4,4-trifluorobutyl)carbamoyl]-1-methylindol-3-yl]methyl]-3-methoxy-N-[(2-methylphenyl)sulfonyl]benzamide (38p, ZENECA ZD 3523),which has been chosen for clinical evaluation. This compound exhibited a K-i of 0.42 nM for displacement of [H-3]LTD(4) on guinea pig lung membranes, a pK(B) Of 10.13 +/- 0.14 versus LTE(4) on guinea pig trachea, and an oral ED(50) Of 1.14 mu mol/kg opposite LTD(4)-induced bronchoconstriction in guinea pigs. The R enantiomer was found to be modestly more potent than the S enantiomer 38o. Modification of the amide substituent to afford achiral compounds was unsuccessful in achieving comparable levels of activity. Profiling of 38p opposite a variety of functional assays has demonstrated the selectivity of this compound as a leukotriene receptor antagonist. The enantioselective synthesis of 38p, which employed a diastereoselective alkylation of (4R,5S)-3-(1-oxo-4,4,4-trifluorobutyl)-4-methyl-5-phenyl-2-oxazolidinone (27) as the key step to establish the chirality of the amide substituent, provided an efficient route for generating 38p in >99% enantiomeric purity.