Bioactive seco-abietane rearranged diterpenoids from the aerial parts of Salvia prionitis

[Display omitted] •18 compounds including 5 previously undescribed and 13 known seco-abietane rearrange diterpenoids were isolated from the aerial parts of Salvia prionitis.•Absolute stereochemistries of prionidipene A-C (1–3) were confirmed by evaluation of experimental and calculated electronic circular dichroism (ECD) spectra.•Prionidipene B (2) was the first example of pinacol rearrangement derivatives and was proposed plausible biogenetic pathway.•Nine compounds showed inhibitory NO activity in RAW264.7 Cells. Five previously undescribed 4,5-seco-abietane rearrange diterpenoids (1–5, Prionidipene A-E) were isolated from the aerial parts of Salvia prionitis, along with thirteen known seco-abietane diterpenoids (6–18). The structures of 1–5 were elucidated mainly based on analysis of NMR and MS data. The absolute configurations of 1–3 were determined by evaluation of experimental and calculated electronic circular dichroism (ECD) spectra. Putative biosynthetic pathways toward the formation of 1 and 2 are proposed. The nitric oxide (NO) production inhibitory effects of all isolates in lipopolysaccharide (LPS)-induced in RAW 264.7 cells were evaluated. Interestingly, compounds 4 and 9 with a furan-ring showed potent inhibitory activity with IC50 values of 14.56 and 15.11 μM, respectively.