Anti-inflammatory and cytotoxic activities of constituents isolated from the fruits of Ziziphus jujuba var. inermis Rehder

Three new sesquilignans, zijusesquilignans A-C (1–3), together with fifteen known compounds (4–18), were isolated from fruits of Ziziphus jujuba var. inermis Rehder (Rhamnaceae). Their chemical structures were established using spectroscopic analyses including 1D- and 2D-NMR, HR-EIMS, and ECD spectra. These compounds were assessed for their inhibitory effects on nitric oxide (NO) production. Of these compounds, 1–3 and 17 displayed inhibitory effects on NO production, with IC₅₀ values ranging from 18.1 to 66.4 μM. Pretreatment with 1 and 17 significantly suppressed LPS-induced expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein in cells. Moreover, compounds 1–3, 7, 9, and 17 exhibited cytotoxic activities against three human tumor cell lines, with IC₅₀ values ranging from 8.4 to 44.9 μM.