“… alanine of three residues near the pore helix (… Val659) reduced channel sensitivity to block by dofetilide and E-4031, effects identical with those reported previously for two other methanesulfonanilides, (+)- N -[1′ -(6-cyano-…(R)-hydroxyspiro(2H -1-benzopyran-2,4′ -piperidin)-6-yl]-methanesulfonamide] monohydrochloride (MK-499) and ibutilide.”