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A series of novel derivatives based on mogrol were designed and synthesized in attempt to improve anti-lung cancer activity. The cytotoxicity against human lung cancer cells including A549 and NCI-H460 were performed by Cell Counting Kit-8 (CCK8) assay in vitro. The screening result showed that compound 8f exhibited the strongest activity with an IC50 value of 4.47 μM against A549 cell, and could induce the cell apoptosis in a dose-dependent manner and arrest cell cycle at G0/G1 phase. Besides, compound 8f displayed anti-proliferation effect on A549 cell through inhibiting phosphorylation of signal transducer and activator of transcription 3 (STAT3). Furthermore, compared with morgol, compound 10a significantly improved the cytotoxicity against NCI-H460 with the IC50 value of 17.13 μM. The research stimulated the development of potential therapeutic agent for lung cancer from the natural mogrol.

In the course of a phytochemical and chemotaxonomical investigation for the Castanopsis (Fagaceae) species, fifteen compounds, including two triterpene hexahydroxydiphenoyl esters (1 and 2), seven gallotannins (3–9), three flavonoids (10–12), and three other compounds (13–15) were isolated from the leaves of Castanopsis fargesii Franch. Their structures were elucidated by means of spectroscopic methods and in comparison with published data. All these compounds were obtained from this species for the first time. Moreover, ethyl glucopyranoside (15) was firstly isolated from the genus Castanopsis. 6-O-Galloyl-β- d -glucose (3) and 3,4′,5,7-tetrahydroxyflavone (11) have not been reported from any species in Fagaceae family. The chemotaxonomic significance of these compounds was summarized.

A new C25 terpene consisting of C15 and C10 terpenes, sarcaglabrin A, and two new sesquiterpene dimers, sarcaglabrins B and C, were isolated from the aerial parts of a medicinal plant Sarcandra glabra used in Guangxi Zhuang Autonomous Region, China. Their structures were elucidated on the basis of detailed spectroscopic analyses including calculation of the ECD spectrum. Sarcaglabrin A was assigned as a conjugate of lindenane type sesquiterpene and ocimene type monoterpene, while sarcaglabrins B and C were elucidated to be lindenane sesquiterpene dimers. Their cytotoxicity against human cancer cell lines were evaluated.

Six new limonoids, munropins A−F (1–6), were isolated from the aerial parts of a Chinese medicinal plant, Munronia pinnata (Meliaceae). The structures of 1–6 were assigned by detailed analyses of their spectroscopic data. Munropins A (1) and B (2) are limonoids possessing a prieurianin skeleton with α,β-unsaturated γ-lactam moieties at C-17. Munropins C (3), D (4), and E (5) are also prieurianin type limonoids with an α,β-unsaturated γ-lactone moiety, an acetyl group, and an acetoxyacetyl group at C-17, respectively. Munropin F (6) was assigned as a nimbolinin type limonoid with a γ-hydroxy-α,β-unsaturated γ-lactone moiety.

Three new nor-clerodane diterpenoids, crotoeurins A-C (1-3), together with four known ones were isolated from the twigs and leaves of Croton euryphyllus. Among them, crotoeurin A (1) is a new nor-clerodane diterpenoid dimer with a unique cyclobutane ring via a [2+2] cycloaddition. Their structures were elucidated by spectroscopic analyses and the stereochemistry of 1 was confirmed by single-crystal X-ray diffraction analysis. Compounds 1-3 exhibited neurite outgrowth-promoting activity on NGF-mediated PC12 cells at concentration of 10 mu M. (C) 2015 Elsevier Ltd. All rights reserved.

In the course of a chemotaxonomical study of Castanopsis species (Fagaceae), detailed investigation of the leaves of C. sclerophylla led to isolation of three new phenolic compounds together with 62 known compounds. The structures of the new compounds were elucidated as 2-O-galloyl-O-4,6-(S)-valoneoyl-d-glucose (1), 6-O-galloyl-1-O-vanilloyl-β-d-glucose (2), and 4″-O-galloylchestanin (3) by means of spectroscopic analyses and enzymatic hydrolysis with tannase. Comparison with other Castanopsis species indicated that C. sclerophylla characteristically accumulates chlorogenic acid and a dimeric ellagitannin, rugosin E. Triterpene hexahydroxydiphenoyl esters, which are major constituents of C. cuspidata var. sieboldii, C. hystrix, and C. fissa were not detected., Phytochemistry Letters, 5(1), pp.158-161; 2012

Triterpene hexahydroxydiphenoyl (HHDP) esters have only been isolated from Castanopsis species, and the distribution of these esters in nature is of chemotaxonomical interest. In this study, the chemical constituents of the leaves of Castanopsis fissa were examined in detail to identify and isolate potential HHDP esters. Together with 53 known compounds, 3,4-di-O-galloyl-1-O-purpurogallin carbonyl quinic acid (1) and 3,24-(S)-HHDP-2α,3β,23,24-tetrahydroxytaraxastan-28,20β-olide (2) were isolated and their structures were elucidated by spectroscopic and chemical methods. The polyphenols of the leaves were mainly composed of galloyl quinic acids, triterpenes HHDP esters, ellagitannins and flavonol glycosides. In particular, the isolation yields of 1,3,4-trigalloyl quinic acid and compound 2 were 1.53% and 0.27%, respectively, from the fresh leaves. The presence of lipid soluble HHDP esters of oleanane-type triterpenes as one of the major metabolites is an important chemotaxonomical discovery. Lipase inhibition activities and ORAC values of the major constituents were compared. The triterpene HHDP ester showed moderate lipase inhibition activity and myricitrin gave the largest ORAC value., Phytochemistry, 72(16), pp.2006-2014; 2011

In this study, we report three novel naturally occurring compounds, blapsins A (1) and B (2), and blapsamide (3) from the ethanol extract of the stink beetle, Blaps japanensis. The structures of these compounds were determined using spectroscopic methods. Compound 3 is a phenolic compound bearing a formamido group in the structure. Functional studies revealed that compounds 1 and 2 potently inhibited 14-3-3 protein-protein interactions (PPIs) with IC50 values of 9.2 and 10.0 mu M as determined by an ELISA assay, and 2.0 and 2.5 mu M in an FP assay, respectively. These compounds represent the first example of natural small-molecule 14-3-3 inhibitors. (C) 2012 Elsevier Ltd. All rights reserved.