A new bicyclo [3.3.1]nonadienemethanol-type lignan from the leaves of Taxus wallichiana Zucc

Following an α-glucosidase inhibitory activity-guided phytochemical study, a rare new bicyclo[3.3.1]nonadienemethanol-type lignan named 9,9'-oxidolanceolatanin B (1) and four known lignans, lanceolatanin B (2), pinoresinol (3), syringaresinol (4), and medioresinol (5), were isolated from a CHCl₃-soluble fraction of Taxus wallichiana Zucc. leaves. The absolute configuration of 9,9'-oxidolanceolatanin B was elucidated based on NMR spectroscopic interpretation and ECD data. All isolated compounds 1-5 showed stronger α-glucosidase inhibitory potency than the positive control, acarbose. This data could support the conceit that Taxus wallichiana leaves could be a promising source for plant-based anti-diabetic drug discovery.