Caged polycyclic polyprenylated acylphloroglucinols as Ca(v)3.2 low voltage-gated Ca2+ channel inhibitors from Hypericum curvisepalum

Five caged polycyclic polyprenylated acylphloroglucinols including an unprecedented octahydro-2,5-methanoindene skeleton (1) were discovered from Hypericum curvisepalum. Biologically, 1 and 2 are potent Ca(v)3.2 T-type Ca2+ channel inhibitors with negligible effect on the cardiovascular antitarget, the human ether-A-go-go-related gene potassium channel. Additionally, 2 indicates strong antinociception in the mouse acetic acid writhing test.