Two ring opened oxetane taxoids containing a C-20 benzoyloxy group from the roots of Taxus wallichiana Zucc.

Two new taxanes, named wallitaxane G (1) and H (2), were isolated from the roots of Taxus wallichiana (Taxaceae), together with nine known compounds (3-11). Their structures were elucidated on the basis of NMR spectroscopic analysis and the relative configurations of 1 and 2 were determined based on NOESY data. Wallitaxane H (2) showed the most potent cc-glucosidase inhibitory activity, with an IC50 value of 16.1 M. Plausible biosynthetic pathways for the formation of 1 and 2 were proposed based on oxetane ring-opening and benzoyl migration. (C) 2017 Elsevier Ltd. All rights reserved.