3-Alkyl- and 3-aryl-7H-furo[3,2-g]chromen-7-ones as blockers of the voltage-gated potassium channel Kv1.3.

3-Alkyl- and 3-aryl-7H-furo[3,2-g]chromen-7-ones were synthesised and studied for their effects on voltage-gated K+ and Na+ channels of the neuroblastoma cell-line N1E-115 and K+ channels of L-929 mouse-fibroblasts, stably transfected with mKv1.3. All furocoumarins tested showed Kv channel blocking activities, the most potent one in a half-blocking concentration of 0.7 microM.