A new diterpene and bioactivities of labdanes isolated from Buddleja marrubiifolia

Anti-inflammatory and antioxidant activities of chemical constituents from the flower buds of Buddleja officinalis

Five new glycosides including mimenghuasu A and B (1-2), isolinarin (3), cyclocitralosides A and B (4-5), along with forty-seven known compounds were isolated from the flower buds of Buddleja officinalis. These structures were elucidated by extensive spectroscopic analysis (UV, IR, 1 D, 2 D NMR, and MS spectra). The anti-inflammatory activities of the isolated compounds were determined by enzyme-linked immunosorbent assay (ELISA) on the expression of TNF-α (LPS-activated RAW264.7 cells) and MTT experiment on LPS-induced HUVECs proliferation effects. Good suppressive effects on the expression of TNF-α were shown by 4 and 5 with IC₅₀ values of 19.35 and 22.10 μM, respectively, compared to positive control indomethacin (IC₅₀ 16.40 μM). In addition to this, some isolated compounds exhibited excellent antioxidant activities including compounds 16, 18, 29, 39, and 47 (IC₅₀ μM: 82.59, 72.94, 33.65, 46.67, and 20.81, respectively) with almost the same or stronger potency with reference to vitamin C as positive control (IC₅₀ 81.83 μM).