Isomorellinol

World J Gastroenterol. 2010 May 14;16(18):2235-43.

Apoptotic activity of caged xanthones from Garcinia hanburyi in cholangiocarcinoma cell lines.[Pubmed: 20458760 ]

To investigate the growth inhibitory mechanism of four caged xanthones from Garcinia hanburyi in cholangiocarcinoma (CCA) KKU-100 and KKU-M156 cells.
METHODS AND RESULTS:
Four caged xanthones, selected on the basis of their anticancer potency and chemical structure diversities (i.e. isomorellin, Isomorellinol, forbesione and gambogic acid) were used in this study. Growth inhibition of these caged xanthones was determined using the sulforhodamine B assay. Induction of apoptosis was assessed by observing cell morphology, ethidium bromide and acridine orange staining and DNA fragmentation assay. Levels of apoptotic-related gene and protein expressions were determined by a real-time reverse transcriptase polymerase chain reaction and Western blotting analysis, respectively.
CONCLUSIONS:
Our findings for the first time demonstrate that four caged xanthones induce apoptosis in CCA cells which is mediated through a mitochondria-dependent signaling pathway.

Anal Chim Acta. 2008 Nov 23;629(1-2):104-18.

Analysis of caged xanthones from the resin of Garcinia hanburyi using ultra-performance liquid chromatography/electrospray ionization quadrupole time-of-flight tandem mass spectrometry.[Pubmed: 18940327 ]

On-line ultra high-performance liquid chromatography (UHPLC) coupled with electrospray quadrupole time-of-flight tandem mass spectrometry (ESI-QTOF-MS/MS/MS) has been developed for the analysis of a series of caged xanthones in the resin of Garcinia hanburyi.
METHODS AND RESULTS:
The fragmentation of protonated molecular ions for 12 known cadged xanthones was carried out using low-energy collision-induced electrospray ionization tandem mass spectrometry. It was found that Retro-Diels-Alder rearrangement occurred in the CID processes and produced the characteristic fragment ions, which are especially valuable for the identification of this class of xanthones. The fragmentation differential between some cis-, trans-isomers was uncovered. Computation methods were utilized to rationalize the observed MS behaviors.
CONCLUSIONS:
On-line UHPLC-ESI-MS/MS/MS method has proved to be rapid and efficient in that within 6min, 15 caged scaffold xanthones, including three pairs of epimers and four pairs of isomers in gamboges, were effectively separated and identified. Among them, two known, namely isogambogenin (13) and Isomorellinol (14) and one likely new caged Garcinia xanthones from the Garcinia hanburyi were tentatively characterized based on the tandem mass spectra of known ones.