Four new alkaloids from the roots of Dactylicapnos scandens.

Four new alkaloids (1 − 4), together with five known ones (5 − 9), were isolated from the bulbs of Dactylicapnos scandens. The structures were determined by analysis of their spectroscopic data and quantum-chemical calculations. All the isolates were tested for their ability to modulate neuronal Ca2+ mobilization in primary cultured neocortical neurons. Compound 8 inhibited spontaneous Ca2+ oscillations at low micromolar concentrations. [ABSTRACT FROM AUTHOR]