gambogic-acid and xanthone

Natural compounds have enormous biological and clinical activity against dreadful diseases such as cancer, as well as cardiovascular and neurodegenerative disorders. In spite of the widespread research carried out in the field of cancer therapeutics, cancer is one of the most prevalent diseases with no perfect treatment till date. Adverse side effects and the development of chemoresistance are the imperative limiting factors associated with conventional chemotherapeutics. For this reason, there is an urgent need to find compounds that are highly safe and efficacious for the prevention and treatment of cancer. Gambogic acid (GA) is a xanthone structure extracted from the dry, brownish gamboge resin secreted from the Garcinia hanburyi tree in Southeast Asia and has inherent anti-cancer properties. In this review, the molecular mechanisms underlying the targets of GA that are liable for its effective anti-cancer activity are discussed that reveal the potential of GA as a pertinent candidate that can be appropriately developed and designed into a capable anti-cancer drug.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Cell Line, Tumor; Garcinia; Humans; Models, Biological; Molecular Structure; Neoplasms; Xanthones

With bioassay- and chemistry-guided fractionation, seven new caged prenylxanthones including two scalemic mixtures, epiisobractatin (1), 13-hydroxyisobractatin (2), 13-hydroxyepiisobractatin (3), 8-methoxy-8,8a-dihydrobractatin (4), 8-ethoxy-8,8a-dihydrobractatin (5), garcibracteatone (6), and 8-methoxy-8,8a-dihydroneobractiatin (7), and the eight known compounds 8-15 were isolated from the leaves of Garcinia bracteata. The structures were unambiguously elucidated through analysis of spectroscopic data. The 2D structures and relative configurations of 1 and 5 were confirmed by X-ray crystallographic analysis. The separation of the enantiomers of 1-5 was accomplished by chiral-phase HPLC. The absolute configurations of the enantiomers of 1 and 5 were assigned by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. The absolute configurations of the related compounds were determined via comparisons of their ECD data with those of the enantiomers of 1 and 5, respectively. Notably, compound 7, with a neo caged skeleton, is the first representative of a novel type of caged xanthone lacking a Δ

Topics: Antineoplastic Agents, Phytogenic; Biological Assay; Cell Line, Tumor; Cell Proliferation; Chromatography, High Pressure Liquid; Circular Dichroism; Crystallography, X-Ray; Garcinia; HL-60 Cells; Humans; K562 Cells; Plant Leaves; Structure-Activity Relationship; Xanthones

DDO-6101, a natural-product-like caged xanthone discovered previously in our laboratory based on the pharmacophoric scaffold of Garcinia natural product gambogic acid (GA), shows potent cytotoxicity in vitro but poor efficacy in vivo due to its poor druglike properties. In order to improve the druglike properties and in vivo cytotoxic potency, a novel series of 19 prenyl group-modified derivatives of DDO-6101 was synthesized and evaluated for their in vitro antitumor activity and druglike properties. The SAR and SPR information of these compounds was also obtained. In the light of the in vitro antitumor activity and druglike properties such as aqueous solubility and permeability, compound 6f (named as DDO-6306) was advanced into in vivo efficacy experiment. The results showed that DDO-6306 is more potent than DDO-6101 in vivo and is a promising antitumor candidate for further evaluation.

Topics: Animals; Antineoplastic Agents; Apoptosis; Biological Products; Body Weight; Cell Line, Tumor; Cell Membrane Permeability; Cell Proliferation; Drug Screening Assays, Antitumor; Garcinia; Humans; Mice; Structure-Activity Relationship; Transplantation, Heterologous; Xanthones

The MS and multi-MS spectra of gambogic acid and gambogenic acid in positive ion detection mode were analyzed by electrospray ion trap mass spectrometry (ESI-QITMS) and their cleavage patterns were summarized. Gamboge samples were separated by a Kromasil C18 column and analyzed by HPLC-PDA and MS. Sixteen xanthones could be separated and detected, A collision induced dissociation (CID) experiment was carried out. Molecular weight and UV spectra with of these compounds were obtained. Ten xanthone compounds in Gamboge were identified by online photodiode array detection-MS(n) and by comparing with data from literature. It is expected to develop a comprehensive quality control method for this kind of compounds in commonly used herbal preparation especially in structure analysis of trace substances.

Topics: Chromatography, High Pressure Liquid; Garcinia; Molecular Structure; Plants, Medicinal; Quality Control; Spectrometry, Mass, Electrospray Ionization; Xanthones