Chemical constituents from Ginkgo biloba leaves and their cytotoxicity activity

One novel neoligan glucoside, Ginkgoside B (1), and one new glucose ester, 6-O-(4-hydroxyhydrocinnamoyl)-d-glucopyranose (2), along with nine known compounds (3–11) were isolated from the ethanol extract of Ginkgo biloba leaves. Their structures were elucidated by combination of spectroscopic analyses and alkaline methanolysis. The absolute configuration of compound 1 was determined by single-crystal X-ray diffraction. All the isolated compounds were evaluated for their cytotoxicity activities, and compound 11 exhibited IC50 values of 36.20 and 58.95 μM against 5637 and HeLa cell lines, respectively.