Diterpenes from the Trunk of Abies holophylla and Their Potential Neuroprotective and Anti-inflammatory Activities

Eleven new abietane-type diterpenes, holophyllins D–N (1–11), and 17 known analogues (12–28), were isolated from a MeOH extract of the trunk of Abies holophylla. The chemical structures of 1–11 were determined through spectroscopic data analysis, including NMR (1H and 13C NMR, DEPT, 1H–1H COSY, HMQC, HMBC, and NOESY) and HRFABMS methods. All isolated compounds (1–28) were evaluated for their cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-116), for their potential neuroprotective effects through induction of nerve growth factor in C6 glioma cells, and for their effects on nitric oxide levels in lipopolysaccharide-stimulated murine microglia BV2 cells.