2-arylethenesulfonamide derivatives, a novel class of ETA-selective endothelin (ET) receptorantagonists, including the compounds 1a, b. Compound 1a showed excellent oral antagonistic activities and pharmacokinetic profiles, and the monopotassium salt of 1 (YM-598 monopotassium) is in clinicaltrials. In this paper, we wish to report the investigation of the further details of structure-activity relationships (SARs)