Sulfonate chalcone as new class voltage-dependent K+ channel blocker

Chalcone derivatives 1–17 were synthesized and their voltage-dependent K+channel inhibitory activities were investigated. The effective K+ channel blockers were shown to be sulfonate chalcones 9–17, in which the sulfonyloxy group is placed on the A-ring. The 3′-(p-aminobenzene-sulfonylhydroxy)-4-hydroxychalcone 17 (IC50 = 0.51 ± 0.05 μM) was the most potent K+ channel blocker.