Daphnane-type diterpenoids from Stellera chamaejasme L. and their inhibitory activity against hepatocellular carcinoma cells.

Daphnane-type diterpenoids, which are scarce in nature, exhibit potent growth-inhibitory activities against various cancer cells. To identify more daphnane-type diterpenoids, the phytochemical components in the root extracts of Stellera chamaejasme L. were analysed in this study using the Global Natural Products Social platform and the MolNetEnhancer tool. Three undescribed 1α-alkyldaphnane-type diterpenoids (1-3; named stelleradaphnanes A-C) and 15 known analogues were isolated and characterised. The structures of these compounds were determined using ultraviolet and nuclear magnetic resonance spectroscopy. The stereo configurations of the compounds were determined using electronic circular dichroism. Next, the growth-inhibitory activities of isolated compounds against HepG2 and Hep3B cells were examined. Compound 3 exhibited potent growth-inhibitory activities against HepG2 and Hep3B cells with half-maximal inhibitory concentration values of 9.73 and 15.97 µM, respectively. Morphological and staining analyses suggested that compound 3 induced apoptosis in HepG2 and Hep3B cells.

Stellerasespenes A‒E: Sesquiterpenoids from Stellera chamaejasme and their anti-neuroinflammatory effects.

Five undescribed sesquiterpenoids stellerasespenes A‒E and four reported congeners were isolated from the roots of Stellera chamaejasme. The structures were elucidated by comprehensive spectroscopic analyses together with X-ray single crystal diffraction and theoretical calculations. The structure of holosericin B was revised. All the isolated compounds were evaluated for NO production in murine microglial BV2 cells induced by LPS. Stellerasespene A showed better inhibitory activity than the positive control minocycline, inhibiting NO production and overexpression of pro-inflammatory cytokine IL-1ß in LPS-activated BV2 cells.

Guaiane-type sesquiterpenoids from the roots of Stellera chamaejasme L. and their neuroprotective activities.

Nine undescribed guaiane-type sesquiterpenoids stelleraterpenoids A‒I, along with seven reported congeners, were isolated and identified from the 70% EtOH extract of the roots of Stellera chamaejasme L. Their chemical structures were elucidated on the basis of various spectral data. The relative configurations were determined by their NOESY spectra and comparison between their experimental and calculated NMR data. The absolute configurations were established by the comparison between the experimental and calculated ECD spectra and further by X-ray single-crystal diffraction analysis. The neuroprotective effects of these compounds on the H2O2-induced damage in human neuroblastoma SH-SY5Y cells were evaluated. Stelleraguaianone B exhibited the better activity with 71.62% cell viability compared to the positive control Trolox (65.05%) at 12.5 µM, which might be achieved by inhibiting the apoptosis of SH-SY5Y cells based on an annexin V-FITC/PI staining experiment.