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Three new isochromenes, (5-methoxy-7-prenyl-1H-isochromen-3-yl)methanol (1), 3-(3-(hydroxymethyl)-5-methoxy-1H-isochromen-7-yl)propan-1-ol (2), and (5-methoxy-7-methyl-1H-isochromen-3-yl)methanol (3), along with three known analogues (4–6) were isolated from the fermentation products of a Nicotiana tabacum-derived endophytic fungus Aspergillus versicolor. Their structures were elucidated by spectroscopic methods, including extensive 1 D and 2 D NMR techniques. Compounds 1–3 and 6 were evaluated for their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compound 2 exhibited high anti-TMV activity with inhibition rate of 46.4%, and this rate is higher than that of positive control. Compounds 1, 3, and 6 also showed potential anti-TMV activity with inhibition rates of 28.6, 30.5, and 26.2%, respectively. The IC50 of compounds 1–3 and 6 were also tested, and showed IC50 values of 49.3, 22.4, 42.2, and 54.1 µM, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] Three new anthraquinones (1 – 3), together with four known analogues (4 – 7) were isolated from the twigs of Cassia auriculata Linn.. Their structures were elucidated by extensive spectroscopic analysis and comparison of spectroscopic data with those reported in literatures. All compounds were tested for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. Compounds 1 , 2 and 7 showed modest antibacterial activity against MRSA with MIC values of 4.2, 5.0, 4.7 μ g/mL, and compounds 3 , 4 , 5 and 6 showed weak antibacterial activity against MRSA with MIC valves of 9.2, 7.6, 7.1, 9.6 μ g/mL, respectively. [ABSTRACT FROM AUTHOR]

Three new diphenyl ethers (1-3), together with four known isopentylated diphenyl ethers derivatives (4-7), were isolated from the fermentation products of an endophytic fungus Phomopsis fukushii. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1-3 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results revealed that compounds 1 and 2 showed strong inhibitions with inhibition zone diameters (IZD) of 20.2 ± 2.5 mm and 17.9 ± 2.2 mm, respectively. Compound 3 also showed good inhibition with IZD 15.2 ± 1.8 mm. The IZD data of compound 1 is close to that of positive control with IZD 21.9 ± 2.1 mm. [ABSTRACT FROM AUTHOR]

An endophytic Phomopsis fukushii was isolated from the rhizome of Paris polyphylla var. yunnanensis , Diaporthaceae family, and three new ( 1–3 ) and four known napthalene derivatives ( 4 – 7 ) were isolated from the fermentation products of this fungus. Their structures were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Compounds 1–3 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity with vancomycin as positive control. The results showed that compounds 1–3 showed good inhibitions with MCI valves of 4, 4 and 6 m g/mL, respectively. [ABSTRACT FROM AUTHOR]

A 'turn-on' pattern Fe3+-selective fluorescent sensor was synthesized and characterized that showed high fluorescence discrimination of Fe3+ over Fe2+ and other tested ions. With a 62-fold fluorescence enhancement towards Fe3+, the probe was employed to detect Fe3+ in vivo in HeLa cells and Caenorhabditis elegans, and it was also successfully used to elucidate Fe3+ enrichment and exchange infected by innexin3 (Inx3) in hemichannel-closed Sf9 cells. [ABSTRACT FROM AUTHOR]

An Hg2+-selective fluorescent sensor ( 1) bearing pyrene as a fluorophore was synthesized. A sandwich-stacking binding mode was formed during the binding process, which increased the excimer fluorescence 22-fold at 490 nm. Compound 1 was successfully applied in in vivo imaging to trace the enrichment and distribution of mercury in the nervous system, digestive system, and reproductive system of Caenorhabditis elegans, as well as the organs of zebrafish. [ABSTRACT FROM AUTHOR]

Abstract: A 1,8-naphthalimide derivative (1) was intentionally designed and synthesized as a new turn-on fluorescent probe for the detection of zinc ion with high selectivity over other metal ions at pH 7.4 in aqueous media (CH3CN/HEPES, V/V=6:4). The reaction mechanism is attributed to the replacement of the protons of the O–H groups by zinc ion at the binding site and production of fluorescence which is blocked in the photo-induced electron transfer (PET) process. Remarkable enhancement of up to 13-fold in fluorescence intensity with a 38nm red-shift was achieved in the detection of zinc ion. Compound 1 was successfully applied to the fluorescence imaging of zinc ion, with a fluorescence emission color produced in the cell nucleus different from that produced in the cytoplasm, in A549, BEAS-2B, CHO, Hela, and HepG2 cells. Furthermore, cytokinesis-block micronucleus (CBMN) assay was carried out in CHO cells using 1 and zinc ion as the imaging agents, showing that the 1-Zn2+ agent is a nucleic acid selective stain, which could be applied in MN assays in different kinds of cell lines. [Copyright &y& Elsevier]

Abstract: A 1,8-naphthalimide–Cu(II) ensemble was rationally designed and synthesized as a new turn-on fluorescent probe utilizing the ‘chemosensing ensemble’ method for detections of thiols (Cys, Hcy and GSH) with high selectivity over other α-amino acids at pH 7.4 in organic aqueous media (EtOH/HEPES, v/v=9:1). The recognition mechanism was attributed to the remove Cu(II) from the 1,8-naphthalimide–Cu(II) ensemble by thiols and the release of flurescence of ligand 1. Remarkable fluorescence enhancements were therefore observed in the sensing process of thiols by the 1,8-naphthalimide–Cu(II) ensemble. Furthermore, the 1,8-naphthalimide–Cu(II) ensemble was successfully applied to the fluorescence imaging of thiols in CHO cells with high sensitivity and selectivity. [Copyright &y& Elsevier]