Hitherto, we've confirmed the neurotrophic potential of drimane-type sesquiterpenoids via stimulation of neural-like PC-12 cells differentiation in vitro. The novel structures add to the knowledge base on neurotrophic sesquiterpenoids in addition to those already reported in the literature. Apart from the NGF-mediated neurotrophic potential of drimanes herein reported corroborating with previous studies, 8,9 a drimane-type lactone isolated from Inonotus obliquus also induced neuroprotection on H2O2-induced injury in SH-SY5Y cells. Thus, the structureactivity relationship of drimane derivatives and their corresponding mechanisms of action in neuroprotection remain to be established. It will be particularly interesting to study whether the molecules act as NGF substitutes and/or induce NGF synthesis; thus aiding in the development of new neuroprotective medicines.