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In this work, novel Cu2O–DMB nanospheres are developed for NIR-enhanced enzymatic synergistic antibacterial therapy. The bactericidal rate is calculated to be as high as 99.4% against MRSA and 99.8% against AREC, with a high wound healing efficiency.

Z-scheme heterojunction research has become a hotspot in the field of photocatalysis owing to the strong oxidative and reductive capacity for driving photocatalytic reactions. In this work, for the first time, a Z-scheme ternary bismuth phosphate/reduced graphene oxide/protonated g-C3N4 (BiPO4/rGO/pg-C3N4) photocatalyst was fabricated for photocatalytic degradation of tetracycline (TC). The optimal mass ratios of rGO and pg-C3N4 were confirmed as 1.2 wt% and 40 wt%, respectively. This Z-scheme heterojunction exhibited an enhanced TC degrading ability with an 80.0% of TC decomposition after 50 min simulated solar light irradiation, which was 3.3 and 6.3 times that of pg-C3N4 and BiPO4, respectively. Importantly, the internal electric field forced Z-scheme charge transfer of BiPO4/rGO/pg-C3N4 composites, possessing higher charge separation efficiency. The formation of the Z-scheme heterojunction was substantiated by radical scavenging experiments and Mott–Schottky measurements, and it was beneficial for the photocatalytic reaction by accelerating the charge separation and improving the redox ability. Moreover, rGO as cocatalyst could not only provide TC adsorption and catalytic sites but also further promote the charge transfer.

Pathogenic bacteria infections have posed a threat to human health worldwide. Nanomaterials with natural enzymatic activity provide an opportunity for the development of new antibacterial pathways. We successfully constructed iron phosphate nanozyme-hydrogel (FePO

Bacterial infections have become major threats to public health all over the world. With the emergence of antibiotic resistance, it is urgent to develop novel antimicrobial materials to efficiently overcome drug resistance with high bactericidal activity. In this work, UiO-66-NH-CO-MoS

Novel peony-like magnetic graphene oxide (GO)/Fe3O4/BiOI nanocomposites were successfully synthesized through a facile method and characterized by SEM, TEM, XRD, XPS, UV–Vis DRS, BET, FT-IR, and Raman spectra, respectively. The photocatalytic degradation potentiality of GO/Fe3O4/BiOI nanoflowers towards organic dyes Rhodamine B (RhB) and Methylene blue (MB) was demonstrated under the visible-light illumination. Among these samples, GOFB-4 (nFe:nBi = 4:1) possessed the best photocatalytic activity, it could decompose nearly 99.2% of RhB within 80 min and 91.4% of MB within 170 min. Holes and hydroxyl radicals were the two mainly reactive species of GO/Fe3O4/BiOI to degrade RhB and MB under the visible-light irradiation. Furthermore, the photodegradation activity of GOFB-4 nanocomposites against RhB and MB exhibited little loss after five recycles, indicating the essential stability of the photocatalyst.

Mariamide A, a lignanamide isolated from the seeds of Silybum marianum, has demonstrated potential utility as an antioxidant and antidiabetic agent and possesses an 8-O-4′ neolignan skeleton. Herein, a first total synthesis of mariamide A is presented that proceeds in nine steps using vanillin as the starting material. The key steps for the preparation of mariamide A involve an I2-catalyzed bromomethoxylation of an alkene group, a nucleophilic substitution followed by a sequential elimination and a monoacylation reaction.

In this work, an efficient electrochemical biosensor for the detection of DNA damage induced by the interaction of a novel antitumor agent AD-NU was investigated by CV, DPV and SWV methods. The GCE was modified with calf thymus DNA, G-quadruplexes, poly dA and poly dG, respectively. Among all the candidates, compound AD-NU was the optimum ligand because of the minimum energy when binding to DNA or TOP II by molecular docking. The electrochemical analysis revealed the redox mechanism of AD-NU on the GCE surface, which included two consecutive reversible processes of 9,10-diquinone and irreversible redox of nitroso group. The DNA damage caused by AD-NU was investigated by comparing the intensity changes of dGuo and dAdo oxidation peaks in DNA strands, and monitoring the appearance of peak for oxidative product 8-oxoGua. Further confirmation for the interaction between AD-NU and DNA was performed by UV–vis absorption and fluorescence titration, which implied the intercalation of AD-NU into DNA base pairs with a high affinity constant (Kb = 13.7 ×105 M−1). The electrophoresis also revealed the potency of AD-NU to cleave and unwind DNA strands. Finally, AD-NU was proved to have good antiproliferative activity toward tumor cells, with IC50 values of 3.0 μmol ∙ L−1 for A549 cell lines and 3.3 μmol ∙ L−1 for Hela cell lines, superior to MTZ reference.

Bacterial infections have become major threats to public health all over the world. With the emergence of antibiotic resistance, it is urgent to develop novel antimicrobial materials to efficiently overcome drug resistance with high bactericidal activity. In this work, UiO-66-NH-CO-MoS2 nanocomposites (UNMS NCs) are constructed through the amidation reaction. The UNMS NCs are positively charged which is beneficial for capturing and restricting bacteria. Significantly, UNMS NCs possess a synergistic bactericidal efficiency based on near-infrared irradiation (808 nm) regulated combination of photothermal, photodynamic, and peroxidase-like enzymatic activities. Both the photodynamic property and nanozymatic activity of UNMS NCs can lead to the generation of reactive oxygen species. The UNMS NCs show high catalytic activity in a wide pH range and exhibit excellent antibacterial ability against ampicillin-resistant Escherichia coli and methicillin-resistant Staphylococcus aureus with negligible cytotoxicity. Interestingly, due to the 808 nm irradiation-induced hyperthermia in the presence of UNMS NCs, the glutathione oxidation process can be accelerated, resulting in bacterial death more easily. Mice wound models are established to further manifest that UNMS NCs can promote wound healing with good biosafety in living systems.

A photocatalytic electrochemical DNA genosensor based on polyaniline nanofibers and three-dimensional reduced graphene oxide (3D-rGO) modified glassy carbon electrode has been fabricated. It can ultrasensitively detect non-small cell lung cancer gene CYFRA21-1 through photocatalytic reaction. Ethidium bromide is adopted to embed into double stranded DNA (dsDNA) for generating singlet oxygen under green LED irradiation, thereby efficiently cleaving the dsDNA. As a result, the peak currents of [Fe(CN)6]3−/4− increase obviously, due to less blocking of nanocomposites modified electrode and weaker electrostatic repulsion after dsDNA fragmentation. The theoretical LOD is 76.2 aM (3σ) and the peak current is linear with the increasing concentration of complementary DNA target from 0.1 fM to 0.1 µM. This genosensor also possesses good specificity, acceptable stability and reproducibility toward CYFRA21-1, and was successfully applied for the detection of CYFRA21-1 in real serum samples.

The Ramberg-Backlund rearrangement has been successfully utilized to convert readily available α- and α'-hydrogen bearing substituted dibenzyl sulfones into corresponding stilbene derivatives, which is conveniently followed by hydrogenation in the presence of 10% Pd/C to afford the natural bibenzyls.

A convenient and unexpected synthesis of penta-substituted dipyrrole disulfides starting from readily available acyl thioformanilides and acetonitrile derivatives has been developed. The overall process leads to the creation of two C-C bonds, two C-N bonds, and one S-S bond with the concomitant formation of two pyrrole rings and disulfide from the fact that only two reagents need to be mixed together, and it complements the existing pyrrole disulfides chemistry. (C) 2009 Elsevier Ltd. All rights reserved.

A convenient and rapid approach for the syntheses of (-)-kaerophyllin (1), (-)-hinokinin (2) and (±)-isohinokinin (3) was described. The key steps were involved in condensation of aromatic aldehyde and alkylation of the resulting ester to give the complete skeleton of dibenzylbutyrolactone-lignan. Hydrolysis, followed by resolution with quinine, reduction and when appropriate, oxidation gave the title compound. The asymmetric total synthesis of the kaerophyllin (1) was reported for the first time.

A practical eight-step synthesis of lignanamide cannabisin F starting from vanillin is reported for the first time. This synthetic strategy applies the aldol reaction followed by the Wittig reaction to afford the key 8-O-4′-neolignan intermediate diacid. The diacid was condensed with N,O-protected tyramine giving, after deprotection, cannabisin F.

An efficient route to the synthesis of dibenzylbutanediol lignans and their analogues was reported. The syntheses were based on a strategy involving Stobbe condensation and alkylation reaction to give the skeleton of lignan, the resolution of (±)-diacid with quinine, the transformation of functional groups to obtain seven dibenzylbutanediol lignans and one analogue. Among the synthesized lignans, four compounds were natural products. All dibenzylbutanediol lignans and their analogue synthesized were evaluated on HIV Tat transactivation in human epithelial cells, HSV-1 gene and human leukemic, liver, prostate, stomach, and breast cancer cell in vitro , but some compounds displayed weak activity against HIV, HSV and MDA-MB-435 human breast cancer cell. Keywords: Dibenzylbutanediol lignan; Biological activity; Synthesis e-mail: xiaym@qust.edu.cn INTRODUCTION Lignans are a class of secondary plant metabolites produced by oxidative dimerization of two phenylpropanoid units. They are widely distributed in the plant kingdom and have been found in species belonging to more than seventy families. Lignans are found in roots, rhizomes, stems, leaves, seeds and fruits