Study On The Chemical Constituents And Bioactivities Of Fraxinus Sieboldiana

Fraxinus sieboldiana Blume(Oleaceae), is widely distributed in eastern Asia, especially in southern China. Its dried bark has long been used as a folk medicine "Qin Pi" in China and Japan as it is reported to have diuretic, antifebrile, analgesic, and anti-rheumatic activities. By using various chromatographic techniques 102 compounds (see a list above) have been isolated from an ethanolic extract of the twigs of F. sieboldiana, and their structures were elucidated by spectroscopic and chemical methods. Among them, 26 compounds were new, that included a norditerpene glucopyranoside with a novel carbon skeleton, six abietane diterpenes, two sesquiterpenes, seven fatty acid derivatives, two lignans, and eight new aromatic glycosides。Based on analysis of the NMR data of threo-and erythro-arylglycerols in different solvents, an application ofΔδ_C8-C7 values to distinguish threo-arylglycerol and erythro-arylglycerol isomers was proposed.Some compounds were evaluated for their inhibition of TNF-αsecretion of the mouse peritoneal macrophages, against several human cancer cell lines including human colon cancer (HCT-8), hepatoma (Bel7402), stomach cancer (BGC-823), lung adenocarcinoma (A549), and human ovarian cancer(A2780), for their antioxidative activity inhibiting Fe⁺²-cystine induced rat liver microsomal lipid peroxidation and for their cytoprotection of SH-SY5Y cell apoptosis induced by MPP+. At a concentration of 10^-5mol/L, compounds 41, 43, 58, 59, 60, 75, 76, 80, 81, 97 and 99 showed inhibitory actibities to TNF-αsecretion of the mouse peritoneal macrophages with inhibitory rates of 30.8%, 30.9%, 35.3%, 37.9%, 44.3%, 36.7%, 45.4%, 44.3%, 49.2%, 46.9%, and 50.3%. Compounds 47, 59, 87and 92 showed a selective cytotoxicity against human colon cancer (HCT-8) with an IC₅₀ value of 4.12, 4.90, 5.36 and 3.38μM, respectively. At a concentration of 10^-6 mol/L, compounds 47, 59, 86 and 87 showed antioxidative activity inhibiting Fe⁺²-cystine induced rat liver microsomal lipid peroxidation with inhibitory rates of 60%, 88%, 52%, and 51%. At a concentration of 10^-6 mol/L, compound 44 showed cytoprotection of SH-SY5Y cell apoptosis induced by MPP+ with protective rate of 80 %.