Chemical Constituents of Thesium chinense Turcz and Their In Vitro Antioxidant, Anti-Inflammatory and Cytotoxic Activities

Three novel compounds (1–3) along with twenty-six known compounds, two known steroids (4–5) and twenty-four known phenylpropanoids (6–29) were isolated from the whole plant of Thesium chinense Turcz. The structures of the three new compounds were elucidated on the basis of ESI-MS, HR-ESIMS, 1D and 2D NMR, IR, UV spectroscopic data. The absolute stereochemistry of compound 1 was determined by the Gauge-Including Atomic Orbitals (GIAO) method. The in vitro antioxidant, anti-inflammatory and cytotoxic activities of the isolated compounds were evaluated by DPPH radical-scavenging assay, LPS-activated RAW 264.7 cells model and CCK-8 kit, respectively. Compound 11 showed high antioxidant activity with an SC(50) value of 16.2 ± 1.6 μM. Compound 21 showed considerable anti-inflammatory activity with an IC(50) value of 28.6 ± 3.0 μM. Compounds 4 and 5 displayed potent cytotoxic activity against human NCI-H292, SiHa, A549, and MKN45 cell lines, with the compound 4 having IC(50) values of 17.4 ± 2.4, 22.2 ± 1.1, 9.7 ± 0.9, 9.5 ±0.7 μM, and the compound 5 having all IC(50) values less than 0.1 μM in vitro.