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A highly efficient and scalable total synthesis of pesimquinolone I (1) was accomplished in 5 steps with 3 chromatographic purifications.

Four previously undescribed highly oxygenated diterpenoids (1–4), zeylleucapenoids A–D, characterized by halimane and labdane skeletons, were isolated from the aerial parts of Leucas zeylanica. Their structures were elucidated primarily by NMR experiments. The absolute configuration of 1 was established by theoretical ECD calculations and X-ray crystallographic analysis, whereas those for 2−4 were assigned by theoretical ORD calculations. Zeylleucapenoid D (4), with an IC50 value of 38.45 μM in RAW264.7 macrophages and nontoxic activity for zebrafish embryo, and obviously inhibited pro-inflammatory cytokines TNF-α and IL-6 in a dose-dependent manner. Compound 4 inhibited of the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Furthermore, molecular docking analysis indicated the possible mechanism of action for 4 may be bind to targets by hydrogen- and hydrophobic- bond interactions.

A pair of epimers of flavonoid alkaloids, with a pyrrolidone moiety, 2S,5′′R-eupodoratin A (1), 2S,5′′S-eupodoratin A (2), together with two known analogues, drahebephin A (3), drahebephin B (4), were isolated from the flowers of Chromolaena odorata (L.) R.M.King & H.Rob. Their structures were elucidated on the basis of HR-ESI-MS, 1D/2D NMR spectral analyses. The absolute configuration of compounds (1) and (2) was determined by its experimental and calculated electronic circular dichroism (ECD) spectra. All compounds were isolated from the Asteraceae family for the first time. The ABTS·+ scavenging activity of compound (4) reached 93.56% at a concentration of 0.5 mM, while the scavenging capacity of positive control Trolox was 55.94%. In addition, all compounds show moderate antimicrobial activity against Escherichia coli (ATCC, 337304), Staphylococcus aureus (ATCC, 337371) and Candida albicans (ATCC, 186382) with a MIC value of more than 50 µg/mL.

Two unusual phenanthrene derivatives related to aporphine alkaloids, artapilosines A (1) and B (2), as well as two biogenetically related known aporphine alkaloids, (-)-anonaine (3) and (-)-N-acetylanonaine (4), were separated and purified from Artabotrys pilosus. Artapilosine A (1) is the first compound representative of a new class of phenanthrene derivatives having an unprecedented carbon skeleton, in which the six-membered nitrogen-containing heterocyclic structure in a typical aporphine alkaloid was substituted with a unique five-membered carbocyclic ring. This is the first report of the formation of a carbon-carbon bond between C-5 and C-6a in 1 with the loss of the nitrogen atom N-6 in the classic aporphine alkaloid. Artapilosine B (2) is a novel phenanthrene derivative having a hydroxyethyl as a substituent on the phenanthrene ring. Their chemical structures as well as absolute configurations were determined based on analysis of spectroscopic data. Additionally, the potential anti-HIV activities of all isolates 1-4 were appraised. Artapilosines A (1) and B (2) showed notable anti-HIV reverse transcriptase affects, with EC50 values of 20.93 and 125.29 nM, respectively. These results suggested that the discovery of these novel phenanthrene derivatives from A. pilosus with remarkable anti-HIV effects could be essentially important for the researching and developing of new anti-HIV agents.

Three unusual austins-type meroterpenoids penicianstinoids C-E (1-3) were obtained from the mangrove-derived fungus Penicillium sp. TGM112. The structures of 1-3 including absolute configurations were determined by detailed NMR, MS spectroscopic data, X-ray diffraction analysis, and calculated electronic circular dichroism data. Penicianstinoid C (1) was the first austins-type meroterpenoid with a unique 6/6/6/5 rearranged tetracyclic skeleton possessing two unusual spirocyclic moieties (2-oxaspiro[5.5]undeca-4,7-dien-3-one and 6-methylene-2-oxaspiro[4.5]decane-1,4-dione). Penicianstinoid D (2) was an unusual austins-type meroterpenoid with a 6/6/6/6 tetracyclic skeleton containing an octahydro-2H-chromen-2-one unit. Penicianstinoid E (3) possessed a 6/5/6/6/6/5 fused hexacyclic skeleton with an uncommon five-membered ether ring system. The plausible biosynthetic pathway of 1-3 is also proposed. Compounds 1 and 3 inhibited the growth of newly hatched Helicoverpa armigera Hubner larvae with IC50 values of 100 and 200 μg/mL, respectively.

A phytochemical study of the stems of Homalium stenophyllum Merr. & Chun led to the isolation of two new phenolic glycosides (1 and 2) and three known compounds (3–5). The molecular structures of these isolated new phenolic glycosides (1 and 2) were unambiguously established on the basis of comprehensive spectroscopic methods. All the isolated new compounds were evaluated for their cytotoxicities against three human cancer cell lines: HeLa, A-549, and MCF-7 in vitro.

A new biphenyl compound: 5-aldehyde-4'-hydroxy-2,2'-dimethoxybiphenyl (

The phytochemical study on the stems and leaves of

One new epimer pair of long-chain polyenes penicilqueis E (

The present study investigated the chemical constituents and inhibitory activities against α-glucosidase from the seeds of Morinda citrifolia(Noni) by the chromatographic technique and semi-preparative HPLC.Fifteen compounds were isolated from the ethyl acetate extract of the seeds, and their structures were identified on the basis of physiochemical characteristics and spectroscopic data as(9S,2E,4Z,7Z)-9-hydroxydeca-2,4,7-trienoic acid(1), azelaic acid(2), scopoletin(3), ursolic acid(4), quercetin(5), cyclo-(L-Leu-L-Ile)(6), cyclo-(L-Phe-L-Ile)(7), cyclo-(L-Phe-L-Val)(8), cyclo-(L-Leu-L-Val)(9), cyclo-(L-Phe-L-Leu)(10), caffeic acid(11), 3,4-dihydroxycinnamaldehyde(12), p-hydroxybenzoic acid(13), p-hydroxy-cinnamic acid(14), and p-hydroxyphenethyl alcohol(15).Among them, compound 1 was a new fatty acid and compounds 7-10 and 12 were isolated from Morinda plant in the Rubiaceae family for the first time.Compounds 1, 2 and 4-15 were isolated from the seeds of M.citrifolia(Noni) for the first time.All isolated compounds were evaluated for the inhibitory activities against α-glucosidase and compounds 3-5 showed potential inhibitory activity with IC_(50) values of 160, 133, and 120 μmol·L~(-1), respectively.

A new isoflavone (Z)-5,7,4′-trihydroxy-3′-[3-hydroxy-3-methyl-1-butenyl] isoflavone (1) together with seven known isoflavones (2–8) were isolated from the fruits of the Ficus auriculata. Their stru...

Platinum group metals (PGMs) usually exhibit promising aerobic catalytic abilities, providing a green and feasible oxidative desulfurization method. However, often, the PGM nanoparticles (NPs) get leached, and the catalysts are deactivated. In this work, Pt NPs with particle sizes of approximately 4–5 nm were encapsulated effectively and uniformly on the surface of vanadium pentoxide (V2O5) nanosheets (with thicknesses of approximately six atomic layers) through strong metal-support interactions. The synthesized catalysts promote catalytic aerobic oxidation reactions, realizing deep desulfurization (99.1%, l 5 μg g−1) under atmospheric pressure and 110 dC reaction temperature. Remarkable degrees of sulfur removal could be achieved for oils with different initial S-concentrations and substrates. Additionally, the as-prepared catalysts could be recycled for reuse at least seven times.

The phytochemical investigation of the stems of Homalium stenophyllum afforded seven new phenolic glycosides (1−5 and 8−9) and two known compounds (6 and 7). Their structures were elucidated by comprehensive analyses of NMR spectroscopic, mass spectrometric data and chemical hydrolysis. Additionally, their anti-inflammatory activities against the NO production in LPS-induced macrophages were evaluated.

Two new isocoumarins penicimarins L-M (1–2), along with seven known analogues (3–9) were isolated from the mangrove-derived fungus Penicillium sp. MGP11. Compounds 1–2 were established by spectroscopic methods and comparison of their circular dichroism (CD) spectra with the literature. All isolated compounds were evaluated for antioxidant and α-glucosidase inhibitory activities. Compound 8 had better antioxidant activity (IC50 = 4.6 μM) than positive control trolox (IC50 = 12.9 μM). Compounds 5, 8 and 9 exhibited α-glucosidase inhibitory activity with the IC50 values of 776.5, 683.7 and 868.7 μM, respectively.

Two new flavanoids fissistiganoids A and B (1 and 2), together with two known pterocarpans derivatives (3 and 4), were isolated from the stems of Fissistigma tungfangense. The structures of these compounds were elucidated using comprehensive spectroscopic methods. The absolute configurations of fissistiganoids A and B (1 and 2) were determined by comparing their ECD spectra with quantum-mechanics ECD calculations. The inhibitory activities of all compounds against three cancer cell lines HeLa, MCF-7 and A549 were evaluated. Compounds 1–4 showed moderate inhibitory effects on HeLa, MCF-7 and A549 cells with IC50 values ranging from 12.5 to 42.3 μM.

Banana flowers are consumed as a vegetable and traditionally used for managing several health problems including joint pain, a symptom of bone loss. Osteoclasts are key effector cells responsible for bone loss. Some flavonoids in banana flowers, such as quercetin and quercitrin, have been shown to be able to inhibit osteoclastogenesis. Whether banana flowers can inhibit osteoclast formation is unknown. In this study, we prepared the ethyl acetate fraction (FFE-EA) of an ethanolic extract of fresh flowers of Musa nana. Using UPLC-MS/MS analyses, 76 polyphenols were identified in FFE-EA. In RANKL-stimulated RAW264.7 macrophages, FFE-EA inhibited osteoclastogenesis and osteoclastic bone resorption. Mechanistic studies revealed that FFE-EA suppressed NF-κB and MAPK pathways, and lowered mRNA levels of osteoclast formation/function-related genes. These findings suggest that flowers of M. nana could be a source for formulating functional food that benefits bone health.

At present, there are many kinds of H1 receptor antagonists as medicinal foods in clinical application, which can be divided into ethylenediamine antagonist, aminoether antagonist, propylamine antagonist, tricyclic antagonist, piperazine antagonist and piperidine antagonist according to their chemical structures. Herein, the research progresses of allergic reactions of histamine H1 receptor antagonists as medicinal foods were reviewed, and the important aspects of design, synthesis and biological activity of various new compounds were expounded.

A variety of beneficial pharmacological activities have been reported for Se-enriched Grifola frondosa polysaccharides. However, little has been reported on its absorption, and its intestinal uptake and transport profiles remain unknown. Based on our previous research, the aim of this study was to investigate its absorption from two aspects - the polysaccharides and selenium of Se-enriched Grifola frondosa polysaccharides (Se-GFP-22) across Caco-2 cells in vitro. The Caco-2 cells monolayer culture model was successfully constructed to study the transport and uptake of Se-GFP-22. The results revealed that the uptake and transport of Se-GFP-22 were time- and concentration- dependent. Transport studies illustrated that Se-GFP-22 could penetrate Caco-2 cells, mainly mediated through the same routes as endocytosis and selenium in the organic selenium (Se-GFP-22) was more easily absorbed than that in the inorganic selenium control group (sodium selenite). The uptake of Se-GFP-22 may be a macropinocytosis pathway, which was an accumulation from cytoplasm to nucleus process. Se-GFP-22 was a moderately absorbed biological macromolecule testified by the apparent permeability coefficients (Papp) value and transport rates. This work illustrates the characteristics on uptake and transport of Se-GFP-22 and all these results may help to explore the mechanism of polysaccharide absorption in vitro.

It is usually difficult to remove dibenzothiophenes from diesel fuels by oxidation with molecular oxygen as an oxidant. In the study, tungsten oxide was supported on magnetic mesoporous silica by calcination to form a magnetically separable catalyst for oxidative desulfurization of diesel fuel. By tuning different calcining temperatures, the catalyst calcined at 500 °C showed a high catalytic activity with molecular oxygen as the oxidant. Under optimal reaction conditions, the sulfur removal of DBT reached 99.9% at 120 °C after 8 h. Furthermore, the removals of 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene could also get up to 98.2% and 92.3% under the same conditions. The reaction mechanism was explored by selective quenching experiments and FT-IR spectra.

Four new flavone derivatives (1–4), together with six known flavones (5-10), were isolated from the stems of Dracaena angustifolia. The complete structures of new compounds were elucidated by analyses of spectroscopic data and quantum chemistry calculations. Compounds 2, 9 and 10 displayed weak anti-inflammatory activity with IC50 values of 45, 33 and 61 μM, respectively.

Six new limonoids, named hainanxylogranolides A-F (1-6), together with nineteen known ones (7-25) were isolated from the seeds of a Hainan mangrove Xylocarpus granatum. The structures of the new compounds were established by extensive NMR spectroscopic data combined with the DFT and TDDFT calculated electronic circular dichroism spectra. Hainanxylogranolide A (1) is the aromatic B-ring limonoid containing a central pyridine ring and a C-17 substituted γ(21)-hydroxybutenolide moiety. Hainanxylogranolide B (2) belongs to the small group of mexicanolides containing a C

To enhance the biological activity of the natural product geodin (1), isolated from the marine-derived fungus Aspergillus sp., a series of new ether derivatives (2–37) was designed and semisynthesized using a high-yielding one-step reaction. In addition, the insecticidal and antibacterial activities of all geodin congeners were evaluated systematically. Most of these derivatives showed better insecticidal activities against Helicoverpa armigera Hübner than 1. In particular, 15 showed potent insecticidal activity with an IC50 value of 89 μM, comparable to the positive control azadirachtin (IC50 = 70 μM). Additionally, 5, 12, 13, 16, 30 and 33 showed strong antibacterial activity against Staphylococcus aureus and Aeromonas salmonicida with MIC values in the range of 1.15–4.93 μM. The preliminary structure–activity relationships indicated that the introduction of halogenated benzyl especially fluorobenzyl, into 1 and substitution of 4-OH could be key factors in increasing the insecticidal and antibacterial activities of geodin.

The phytochemical investigation on the fruits of

Two unusual phenanthrene derivatives related to aporphine alkaloids, artapilosines A (

Three unusual austins-type meroterpenoids penicianstinoids C-E (

Five new tetralones, daldiniones A-E (1-5), three new chromones, 7-hydroxy-5-methoxy-2,3-dimethylchromone (9), 5-methoxy-2-propylchromone (10), and 7-ethyl-8-hydroxy-6-methoxy-2,3-dimethylchromone (11), and two new lactones, helicascolides D and E (16 and 17), together with nine known metabolites (6-8, 12-15, and 18-19) were isolated from the mangrove-derived fungus Daldinia eschscholtzii HJ004. The structures and absolute configurations of the new compounds were determined by analyzing MS and NMR data and utilizing GIAO based 13C NMR chemical shift calculations and quantum chemical electronic circular dichroism (ECD) calculations. Compounds 9, 13, and 18 showed inhibitory activities against α-glucosidase with IC50 values of 13, 15, and 16 μM, respectively.

One new pentenoic acid derivative, named 1,1′-dioxine-2,2′-dipropionic acid (1) and a new natural product, named 2-methylacetate-3,5,6-trimethylpyrazine (2), along with six known compounds (3–8), were obtained from the Cladosporium sp. JS1-2, an endophytic fungus isolated from the mangrove Ceriops tagal collected in South China Sea. Their structures were elucidated by detailed analysis of comprehensive spectroscopic data, and the structure of 1 was further determined by X-ray diffraction analyses. 13C NMR chemical shifts of structure 2 was further determined by GIAO based 13C NMR chemical shifts calculations. Compounds 1–4 and 6 showed growth inhibition activities against newly hatched larvae of Helicoverpa armigera Hubner with the IC50 values ranging from 100 to 150 μg ml−1. Compounds 1, 2, 4, 6 and 7 showed moderate antibacterial activities against Staphylococcus aureus with the MIC values of 25.0, 12.5, 6.25, 1.25, and 6.25 μg ml−1, respectively.

By introduction of trifluoromethyl and phenyl groups to 2-(2-thienyl)pyridine (thp), four new phosphorescent bis-cyclometalated iridium(III) complexes, (thp)2Ir(tpip), (cf3thp)2Ir(tpip), (cf3btp)2Ir(tpip) and (3-cf3btp)2Ir(tpip) (cf3thp = 2-(thiophen-2-yl)-4-(trifluoromethyl)pyridine, cf3btp = 2-(benzo[b]thiophen-2-yl)-4- (trifluoromethyl)pyridine, 3-cf3btp = 2-(benzo[b]thiophen-3-yl)-4-(trifluoromethyl)pyridine, tpip = tetraphenylimidodiphosphinate), were synthesized and fully characterized. The density functional theory and time-dependent DFT calculations show that the frontier orbitals are mainly localized in the Ir(III) ion and the cyclometalated ligands. Thus, the photophysical properties were dominated by the cyclometalated C∧N ligand, attributed to 3MLCT and 3ILCT transition. These Ir(III) complexes emit in the yellow-to-deep red region with photoluminescence quantum yields in the range 40.5–86.4% in CH2Cl2 solutions at 298 K. The organic light-emitting diodes (OLEDs) using (thp)2Ir(tpip), (cf3thp)2Ir(tpip) and (cf3btp)2Ir(tpip) as yellow, orange and deep red emitters display good electroluminescent performance with low efficiency roll-off. Notably, the device based on (cf3thp)2Ir(tpip) possesses very high EL efficiencies with the maximum luminance efficiency and external quantum efficiency (EQE) of 53.9 cd A−1 and 17.9%, respectively. Furthermore, the EQE for this complex could be still retained as 15.4% at a luminance of 1000 cd m−2.

Seventeen compounds were obtained from the extract of the whole plant of Scutellaria hainanensis C. Y. Wu. Including eleven flavonoids (1–4 and 7–13), two phenylpropanoids (16 and 17), one pyridinium derivative (5), one ester (6), one phenolic derivative (14), and one lignanoid (15). Compound 5 was a synthetic intermediate, newly identified as a natural product. The chemotaxonomic relationship between S. hainanensis C. Y. Wu and other species of genus Scutellaria were also discussed. As a result, the isolated glycoside compounds closely matched the ones obtained in other species of the genus.