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The comprehensive phytochemical research of Lethariella cladonioides (Nyl.) Krog, (Parmeliaceae), a lichen in southwest China, resulted in isolation of eighteen compounds (1–18), including a new phenolic acid 3,5-dihydroxy-4-methylbenzaldehyde (1) and seventeen known compounds, nine phenolic acids (2–10), one dibenzofuran (11), two depsides (12 and 13), one alkane (14), one glucoside (15), two polyols (16 and 17), and one fatty acid (18). The structures of these compounds were assigned by detailed interpretations of spectroscopic data (1D and 2D NMR, HR-ESI-MS) and comparisons with the published data. Among them, 3,5-dihydroxy-4-methylbenzaldehyde (1) is a new one. (−)-hydroxypropan-2′,3′-diol-orsellinate (10) have not been reported from any species in the lichens. Compounds 6, 7, 9, 12, 14, 16 and 18 were firstly isolated from the genus Lethariella (Motyka) Krog. Compounds 2, 6, 7, 9, 10, 12, 14, 16 and 18 were reported from L. cladonioides firstly. The chemotaxonomic significance of these compounds was also discussed.

The coupling of wet scrubber with thermally activated persulfate (PS) for the removal of gaseous p-xylene was studied in the present work. The effects of process parameters (i.e., activation temperature, gas flow rate, PS dosage, and absorption solution pH) on p-xylene removal were studied. The removal efficiency increased with the activation temperature and PS dosage, while decreased with the increase of gas flow rate. The inhibition effect was observed when the pH of the reaction system was alkaline due to the existence of NH3(aq) resulting from ammonium translation. P-xylene was efficiently eliminated under the optimal conditions with a maximum removal efficiency of 78.5%. The most important radicals, namely, SO4 − and HO , were investigated by electron paramagnetic resonance, and the selectivity of SO4 − was determined by quenching tests. HO and SO4 − oxidations accounted for 41.3% and 37.4% of the removal of p-xylene, respectively. The contribution of SO4 − increased with the accumulation of H+. Moreover, the absorption solution reused via adding PS and it still showed perfect removal capacity for p-xylene at the end of each cycle. Finally, a possible degradation pathway of p-xylene was proposed based on the measurements of intermediates being detected in the gas and liquid phases.

Five new isosteroidal alkaloids, walujewine A (1), walujewine B (4), walujewine C (5), walujewine D (6), walujewine E (10) were isolated from the bulbs of Fritillaria walujewii together with seven known isosteroidal alkaloids (2, 3, 7-9, 11, 12). Their structures were elucidated on the basis of IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR spectroscopic data analyses and single-crystal X-ray diffraction. All the isolates were tested for ChE inhibiting activity by the Ellman's method. Compounds 3-5 and 8-10 were potent dual AChE-BChE inhibitors, and compound 1 showed highly selective AChE inhibition. The structure-activity relationship of compounds 1-12 was discussed in details. And kinetic analysis showed that compounds 1, 3-5, and 8-10 were mixed-type reversible inhibitors of AChE, simultaneously binding to the catalytic and peripheral anionic sites, which was verified by in silico docking studies. The docking simulation also showed that active compound 3 and 8 created many interactions with the CAS and PAS gorges of BChE, revealing their mixed-type inhibition. ADMET analysis further confirmed the therapeutic potential of some isosteroidal alkaloids based on their high BBB-penetration.

Objective To isolate and identify bioactive constituents from the stem barks of Illicium difengpi.

A series of new 4-N-phenylaminoquinoline derivatives were designed, synthesized, and their anticholinesterase activities, 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, metal-chelating ability were tested. Among them, compounds 11j, 11k and 11l had comparable inhibition activities to reference drug galantamine both in AChE and in BChE. Especially, compound 11j revealed the most potent inhibition to eeAChE and eqBChE with IC50 values of 1.20 μM and 18.52 μM, respectively. Furthermore, both kinetic analysis of AChE inhibition and molecular docking study indicated that compound 11j was mixed-type inhibitor, binding simultaneously to the catalytic anionic site (CAS) and the peripheral anionic site (PAS) of AChE, and propidium iodide displacement assay showed significant displacement of propidium iodide with compound 11k (25.80%) from PAS of eeAChE. More importantly, compound 11l displayed excellent DPPH radical scavenging activity (84% at 1 mg/mL), and its EC50 value was 0.328 μM. In addition, compounds 11a, 11j, 11k and 11l exhibited obvious biometal chelating abilities toward Al3+, Fe2+, Cu2+ and Zn2+ ions. Taken together, 4-N-phenylaminoquinoline derivatives targeting multiple pathogenetic factors deserve further investigation for treatment of AD.

A new dihydroisocoumarin derivative, R-(−)-heteroscyphide (1), together with three known terpenoid derivatives (2–4), were isolated from the liverwort Heteroscyphus coalitus. Their structures were elucidated by spectroscopic methods and the biogenetic pathway of compound 1 was proposed. Cytotoxic test revealed that they exhibited moderate inhibitory activity to three human tumor cell lines.

Chemical investigation of the fungus Phellinus baumii has resulted in characterization of five previously undescribed hispidin derivatives, phellibaumins A-E (1-5), as well as two pairs of new non-equivalent epimeric benzyl dihydroflavones, methylphelligrin A (9), epi-methylphelligrin A (10), methylphelligrin B (11), and epi-methylphelligrin B (12), together with five known compounds, interfungin B (6), phelligridin H (7), phelligridimer A (8), phelligrin A (13), and epi-phelligrin A (14). Phellibaumin A (1) was a novel hispidin derivative with a unique 3,4-dihydroxybenzofuran unit. These compounds exhibited NF-κB inhibitory activity with IC(50) values of 52.96 μM (1), 41.40 μM (2), 52.92 μM (5), 36.44 μM (9 and 10), and 22.46 μM (11 and 12), respectively.