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Updated: Feb 3, 2026

Formulation and Characterization of Bioactive Agent Containing Nanodisks
Published on: March 17, 2023
Bioactive scalemic caged xanthones from the leaves of Garcinia bracteata
Bao-Jun Zhang1, Wen-Wei Fu2, Rong Wu2
1School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, People's Republic of China; Engineering Research Center of Shanghai Colleges for TCM New Drug Discovery, Shanghai 201203, People's Republic of China; Departement of Pharmacy, Shanghai Putuo District People Hospital, Shanghai 200060, People's Republic of China.
Abstract:
Four pairs of previously undescribed caged xanthones (1-4) and twelve known caged xanthones (5-16) were isolated from the leaf extract of Garcinia bracteata. Their structures were unambiguously elucidated on the basis of spectroscopic methods. The planar structure and relative configuration of 1 was confirmed by X-ray crystallographic analysis. The enantiomers of compounds 1, 2, 4 were further resolved by semi-preparative chiral HPLC, and the absolute configurations of enantiomers of compounds 1 and 4 were determined by measurement and calculation of electronic circular dichroism (ECD) spectra and specific rotations. The inhibitory activities of the isolated compounds against human HeLa, A549, PC-3, HT-29, and WPMY-1 cell lines were assayed, and garcibractatin A (4) showed the most potent inhibitory activities in vitro with IC50 values from 1.11 to 2.93 μM. A preliminary structure-activity relationship has been discussed, and some helpful conclusions have been drawn.
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