A New Tannin from Fruits of Torreya Nueifera with Protein Tyrosine Phosphatase 1B Inhibitory Activity

摘要

A new compound 1,3,6-tri-O-galloyl-2-O-(4-carboxylgalloyl)-beta-D-glucopyranose (1), together with six known compounds (2-7) were isolated from EtOAc-soluble extract of fruits of Torreya nucifera. Their structures were elucidated on the basis of detailed spectroscopic and physico-chemical analyses. All the isolates were evaluated for in vitro inhibitory activity against PTPIB, VHR and PP I. Among them, new compound 1 was found to exhibit selective inhibitory activity on PTPIB with IC50 value 8.9 +/- 1.4 mu M.