Lignans from the Twigs of Litsea cubeba and Their Bioactivities.

ABSTRACT: Litsea cubeba, an important medicinal plant, is widely used as a traditional Chinese medicine and spice. Using cytotoxicity-guided fractionation, nine new lignans 1?9 and ten known analogues 10?19 were obtained from the EtOH extract of the twigs of L. cubeba. Their structures were assigned by extensive 1D- and 2D-NMR experiments, and the absolute configurations were resolved by specific rotation and a combination of experimental and theoretically calculated electronic circular dichroism (ECD) spectra. In the cytotoxicity assay, 7',9-epoxylignans with feruloyl or cinnamoyl groups (compounds 7?9, 13 and 14) were selectively cytotoxic against NCI-H1650 cell line, while the dibenzylbutyrolactone lignans 17?19 exerted cytotoxicities against HCT-116 and A2780 cell lines. The results highlighted the structure-activity relationship importance of a feruloyl or a cinnamoyl moiety at C-9' or/and C-7 ketone in 7',9-epoxylignans. Furthermore, compound 11 was moderate active toward protein tyrosine phosphatase 1B (PTP1B) with an IC₅₀ value of 13.5 ?M, and compounds 4?6, 11 and 12 displayed inhibitory activity against LPS-induced NO production in RAW264.7 macrophages, with IC₅₀ values of 46.8, 50.1, 58.6, 47.5, and 66.5 ?M, respectively.

SUBMITTER: Li X 

PROVIDER: S-EPMC6359749 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature