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Arnequinol A (1), featuring an unprecedented 6/6/3 tricyclic carbon skeleton fused with a heptatomic oxo-bridge, together with arnequinone A (2) bearing a highly conjugated methyl-shifting benzogeijerene skeleton, were isolated from Arnebia euchroma. Their structures were elucidated by extensive spectroscopic methods and quantum chemical calculations of the 13C nuclear magnetic resonance (NMR) data and electronic circular dichroism (ECD) spectra. The plausible biosynthetic pathways for 1 and 2 were presented. In an in vitro test, compound 2 showed potent neuroprotective activity against serum-deprivation induced PC12 cell damage at a concentration of 10 μmol/L.

Three matrine-derived alkaloids, alopecuroidine A (1), alopecuroidine B (2a) and alopecuroidine C (2b) were isolated from the seeds of Sophora alopecuroides. Their structures were elucidated by extensive spectroscopic analyses and X-ray diffraction. Three compounds possess an unprecedented rearranged fused 7/6/5/6 tetracyclic skeleton with a diazacycloheptane structure. Their plausible biosynthetic pathway was also proposed. The anti-proliferative activities of compounds 1 and 2a were examined by the MTT assay. Compound 1 inhibited the viability of human lung cancer A549 cells, having a half maximal inhibitory concentration (IC50) of 7.58 ± 2.47 μmol/L at 72 h. The flow cytometric analysis suggested that 1 inhibited A549 cell growth by inducing apoptosis and cell-cycle arrest. Additionally, 1 induced the loss of mitochondrial membrane potential, elevated intracellular reactive oxygen species, increased the Bax/Bcl-2 ratio, stimulated cleaved-caspase-3 and P53 protein levels, and suppressed the pro-caspase-3 level. Thus, 1 appeared to induce A549 cells apoptosis through a mitochondria-mediated apoptotic pathway.

The 1,2-dibromoethane- and KI-mediated α-acyloxylation of ketones is reported in moderate to good yield without the use of transition metals and strong oxidants. Various acids are well tolerated with wide functional group compatibility. An 1,2-dibromoethane- and KI-catalysed reaction mechanism is proposed based on the results of control experiments.

Four new glycosides including a eudesmane-type sesquiterpenoid (1), a guaiane-type sesquiterpenoid (2), and two C14-polyacetylenes (3, 4) were isolated from the rhizomes of Atractylodes lancea. Their structures were elucidated by means of spectroscopic and spectrometric analyses (UV, IR, 1D and 2D NMR, and HR-ESIMS). The absolute configurations of their aglycones were established based on the experimental and calculated electronic circular dichroism (ECD), whereas those of monosaccharide moieties were determined by the GC method after chiral derivatization. Compound 4 showed weak anti-inflammatory effects on the LPS-induced NO production in microglia BV2 cells at a concentration of 10 μmol L−1.

An efficient and accurate analytical method was developed for the simultaneous determination of 20 synthetic food additives, including three sweeters, seven food colorants, nine synthetic preservatives and caffeine, by high performance liquid chromatography (HPLC) with photodiode array detector (PDA). This method permits the detection of food additives at very low concentrations (0.005–0.150 μg/mL). The applicability was verified by the determination of food additives present in various foodstuffs.

A series of heterocycle-substituted phthalimide derivatives were synthesized. Structurally diverse derivatives with heterocyclic rings, including furan, imidazo[1,2-a]pyridine, 1,3,4-thiadiazine, imidazo[2,1-b][1,3,4]thiadiazine, pyrazole, 1,2,4-triazolo[3,4-b][1,3,4]thiadiazine, thiazole and thiazoline, were obtained by the reactions of α-bromoketone intermediate with various nucleophiles containing oxygen, nitrogen and sulfur atom. Their cytotoxic activity was also evaluated against five human cancer cell lines in vitro .