Chemical constituents from the stem barks of Garcinia multiflora

Triterpene Derivatives from Garcinia oligantha and Their Anti-Cancer Activity

Phytochemical investigations of leaves and twigs from Garcinia oligantha Merr. resulted in the isolation of five undescribed triterpene derivatives (1-5) and six known analogs (6-11). Their structures were determined based on extensive spectroscopic data and high-resolution mass spectra analyses. Compounds 1-11 were tested for their in vitro cytotoxicity against three human cancer cell lines (HeLa, HepG-2, and MCF-7). Compounds 1, 2, 8, and 11 exhibited broad and significant cytotoxicity against the tested cell lines with IC₅₀ values ranging from 5.04 to 21.55 μM. Compounds 5 and 9 showed cytotoxicity against HeLa and MCF-7 with IC₅₀ values ranging from 13.22 to 19.62 μM. The preliminary structure-activity relationship for the 11 isolated compounds is also discussed.

Biphenyls in Clusiaceae: Isolation, structure diversity, synthesis and bioactivity

Clusiaceae plants contain a wide range of biologically active metabolites that have gotten a lot of interest in recent decades. The chemical compositions of these plants have been demonstrated to have positive effects on a variety of ailments. The species has been studied for over 70 years, and many bioactive compounds with antioxidant, anti-proliferative, and anti-inflammatory properties have been identified, including xanthones, polycyclic polyprenylated acylphloroglucinols (PPAPs), benzophenones, and biphenyls. Prenylated side chains have been discovered in many of these bioactive substances. To date, there have been numerous studies on PPAPs and xanthones, while no comprehensive review article on biphenyls from Clusiaceae has been published. The unique chemical architectures and growing biological importance of biphenyl compounds have triggered a flurry of research and interest in their isolation, biological evaluation, and mechanistic studies. In particular, the FDA-approved drugs such as sonidegib, tazemetostat, daclatasvir, sacubitril and trifarotene are closely related to their biphenyl-containing moiety. In this review, we summarize the progress and development in the chemistry and biological activity of biphenyls in Clusiaceae, providing an in-depth discussion of their structural diversity and medicinal potential. We also present a preliminary discussion of the biological effects with or without prenyl groups on the biphenyls.

Stereodivergent Strategy in Structural Determination: Asymmetric Total Synthesis of Garcinol, Cambogin, and Related Analogues

The asymmetric total synthesis of five biologically significant polycyclic polyprenylated acylphloroglucinols (PPAPs), including garcinol and cambogin, was achieved through a highly diastereoselective and stereodivergent strategy. Along the way, an efficient cascade Dieckmann cyclization was employed to construct the bicyclo[3.3.1]nonane core in one step. The synthesis provided a general approach toward the chiral endo-type B PPAPs and their C-30 diastereomers in a single sequence, which resolved the challenges of the absolute configuration determination/structural revision of PPAPs bearing exocyclic stereocenters.

Structural Revision of Guttiferone F and 30-epi-Cambogin

Guttiferone F, a natural polyprenylated polycyclic acylphloroglucinol, was originally assigned as the 30-epimer of garcinol by NMR data analyses. Conversion of guttiferone F in the presence of acid afforded its cyclized form (2a), which was previously assigned as 30-epi-cambogin. However, the absolute configurations of guttiferone F and 2a have not been determined. Reinvestigation of the structures of those two compounds, using X-ray and NMR data analyses and chemical transformation, revealed that the original assignment of the C-30 absolute configuration in guttiferone F and 2a should be inverted. Guttiferone F is indeed garcinol, and 2a, which was previously identified as 30-epi-cambogin, is cambogin.

A pair of new enantiomers of xanthones from the stems and leaves of Cratoxylum cochinchinense

Background

The simple and caged xanthones from Clusiaceae showed significant antineoplastic activity. This study aims to identify structural diverse xanthones and search for novel antitumor natural products from this family plants.

Methods

The structures of new compounds 1a and 1b were elucidated mainly through comprehensive NMR and MS spectroscopic data, and their absolute configurations were determined by the comparison of the experimental and calculated electronic circular dichroism.

Results

A pair of new xanthone enantiomers, (+)- and (-)-cracochinxanthone A (1a and 1b), along with thirty known analogues (2-31), were isolated from extracts of the stems and leaves of C. cochinchinense. Preliminary biological assay of some isolates against HL-60, PC-3, and MDA-MB-231 cancer cell lines.

Conclusion

Some isolated xanthones exhibited high sensitivity against three human malignant cell lines and the structure-activity relationship study showed that the prenyl and geranyl units may play an important role in antitumor activity.

Ferulic Acid and Naturally Occurring Compounds Bearing a Feruloyl Moiety: A Review on Their Structures, Occurrence, and Potential Health Benefits

The ubiquitous compound 4-hydroxy-3-methoxycinnamic acid, also known as ferulic acid (FA), constitutes a bioactive ingredient of many foods that may offer beneficial effects against disorders related to oxidative stress, including cancer, diabetes, and neurodegenerative diseases. This review discusses the antioxidant properties of FA, establishing relationships to several biological activities already described for this natural product. Next, 387 naturally occurring compounds, all isolated from plants and published between 1990 and 2015, the structures of which bear 1 or more feruloyl moieties, are covered in this review along with their structural formulas, botanical sources, and bioactivities. The compounds' distribution, structural patterns, bioactivities, and perspectives on food research are also succinctly discussed.