Phenylethanoid glycosides from the Schnabelia nepetifolia (Benth.) P.D.Cantino promote the proliferation of osteoblasts

An investigation of the n-BuOH fraction of Schnabelia nepetifolia (Benth.) P.D.Cantino led to the isolation and identification of 12 undescribed phenylethanoid glycosides (nepetifosides A–L) and one undescribed phenylmethanoid glycoside (nepetifoside M), together with 23 known compounds. The structures of these compounds were determined by spectroscopic analyses including two-dimensional nuclear-magnetic-resonance (2D-NMR) spectroscopy and chemical-hydrolysis methods. Nepetifoside F exhibited strong activity that significantly increased osteoblast proliferation at three concentrations of 0.1, 1, and 10 μM. Moreover, nepetifoside C and nepetifoside D exhibited moderate activities in promoting the proliferation of osteoblasts at medium and high concentrations of 1 μM and 10 μM, respectively.