Chlorahololides C-F: a new class of potent and selective potassium channel blockers from Chloranthus holostegius

Four unusually fused polycyclic sesquiterpenoid dimers, chlorahololides C-F (1-4), were isolated from the whole plant of Chloranthus holostegius. Their structures and absolute configurations were established by spectroscopic methods, including 2D NMR and CD spectra. Chlorahololides C-F (1-4) exerted potent and selective inhibition on the delayed rectifier (IK) K+ current with the IC50 values of 3.6±10.1, 2.7±0.3, 27.5±5.1 and 57.5±6.1 μM, respectively.

Four potent and selective potassium channel blockers, chlorahololides C-F (1-4) with unusually fused polycyclic scaffold of sesquiterpenoid dimers, were isolated from Chloranthus holostegius.