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Uniform, well-defined cadmium sulfide@cadmium selenide core/shell quantum dots (CdS@CdSe QDs) were, for the first time, successfully synthesized by a solvothermal method and chemical bath growth for photoelectrochemical activities. The as-synthesized CdS@CdSe QDs not only exhibit superior self-powered photoresponse behavior and excellent stability under ambient conditions but also display significantly improved current densities and photoresponsivity compared to those of individual CdS QDs or CdSe QDs, mainly due to the built-in electric field, and thus have great potential in the fields of renewable energy and renewable energy consumption for carbon neutrality target achievement.

Phosphine-mediated reductions of substituted propynoic esters and amides in the presence of water yield the partially reduced α,β-unsaturated esters and amides with high Z-selectivity. The competitive in situ Z to E-isomerization of the product in some cases lowers the Z to E ratios of the isolated α,β-unsaturated carbonyl products. Reaction time and the amounts of phosphine and water in the reaction mixture are the key experimental factors which control the selectivity by preventing or reducing the rates of Z- to E-product isomerization. Close reaction monitoring enables isolation of the Z-alkenes with high selectivities. The computational results suggest that the reactions could be highly Z-selective owing to the stereoselective formation of the E-P-hydroxyphosphorane intermediate.

Thiazoles and benzothiazoles undergo regioselective C2-H chalcogenation via the sequence of thiazole C2-functionalization with phosphines to produce phosphonium salts which in turn react with S- and Se-centered nucleophiles to give products of C2-H chalcogenation and allow for recovery of the starting phosphine. The atom economical sequence proceeds under mild conditions and features broad scope for both the nucleophiles (electron-rich, electron-poor, sterically hindered thiols) and the various substituted benzothiazoles. The access to the substituted medicinally relevant C2-thio benzothiazoles also enables stereoselectivity improvements in the modified Julia olefinations.

Photothermally assisted superhydrophobic sponges play a vital role in the fields of waste oil collection, oil purification, and solar desalination. However, the widely reported superhydrophobic sponges with photothermal efficiency usually suffer from a post-/premodification process of harmful materials, high loading content of photothermal agents, and low photothermal efficiency. Herein, an MXene-based melamine sponge (MS) was facilely fabricated by hydrogen bonding interaction between the amino groups on the skeleton of the MS and the polar groups on the surface of the as-exfoliated 2D MXene Ti3C2Tx nanosheets. Interestingly, the as-fabricated MXene sponge exhibits excellent hydrophobicity and high photothermal efficiency under an extremely low loading of MXene Ti3C2Tx nanosheets (0.1 wt %). Moreover, the highly hydrophobic sponge also possesses a high oil absorption capacity as high as 176 times of its own weight and keeps stable under multiple absorption/desorption cycling tests. Surprisingly, the surface temperature of the MXene sponge can quickly reach 47 °C under illumination and has good reproducibility during multiple light on/off cycles. The excellent photothermal performance and large oil absorption capacity of the MXene sponge endow the highly hydrophobic sponge with fast solvent evaporation speed and high-purity waste oil collection (99.7 wt % dichloromethane) under illumination, which holds great promise for oil/water separation, leaked oil collection, and photo-driven waste oil collection and purification applications. It is envisioned that this work can open a new strategy for new designs of 3D multifunctional sponges for high-performance waste oil collection and purification.

Pyrrolizidine alkaloids and their derivatives often feature interesting biological activities. A class of substituted 2,3-dihydro-1H-pyrrolizin-1-one derivatives has been explored as a potential treatment for Alzheimer's disease, but enantioselective synthesis of these molecules is still elusive. We report that enantioselective N-allylation of N-silyl pyrrole latent nucleophiles with allylic fluorides followed by hydrogenation and diastereoselective Friedel-Crafts cyclization constitute an efficient synthetic route to access enantioenriched substituted 2,3-dihydro-1H-pyrrolizin-1-ones.

Benzothiazoles undergo regioselective C2-H functionalization with triphenylphosphine to form thiazol-2-yl-triphenylphosphonium salts, and these phosphonium salts react with a wide range of O- and N-centered nucleophiles to give the corresponding ethers, amines, and C-N biaryls. The reactions proceed under mild conditions and allow for the recovery of triphenylphosphine at the end of the sequence. In the presence of hydroxide, phosphonium salts undergo disproportionation, resulting in the reduction of the benzothiazole, which is useful for specific C2 deuteration of benzothiazoles.

Generally, the elaborate design of hierarchical micro-nano structures always suffers from high cost and complex procedures, such as laser lithography and plasma etching. Herein, we developed a novel strategy to in-situ fabricate mushroom-like structures constructed by nanowhisker-nanowire hierarchical architectures on copper mesh through a more flexible bottom-up method. The final morphology is highly controlled by adjusting corresponding synthetic conditions. The superhydrophobic copper mesh with a static contact angle of 151.8° and a sliding angle of 3.6° possesses superior anti-fouling and self-cleaning performances towards pollution of daily drinks and dirt. In virtue of the introduction of polydimethylsiloxane (PDMS), the tolerances of superhydrophobic mesh are greatly prolonged more than 24 h in extreme solutions including pH = 1 ~ 14 solutions and 3.5 wt% NaCl solution. Moreover, the superhydrophobic copper mesh presents excellent drag resistance with a high sailing velocity of 25.38 cm s−1 and a large loading capacity (7.34 times) on water. Therefore, the as-prepared mesh exhibits huge potentials for serving as a marine vehicle with a high sailing velocity, which shows satisfying tolerance in extreme environments. It is expected that this research can pave the way to elaborating hierarchical structures on solid surfaces through manageable bottom-up approaches.

A convenient method has been established for the chemoselective synthesis of polyarylated oxazoles from aromatic aldehydes and 2-cyano heteroarenes. The protocol presents a novel one-pot methodology for the synthesis of oxazole derivatives without any metal catalysts or extra oxidants. Photophysical test showed that the polyarylated oxazoles may serve as potential fluorescent materials with blue light-emitting properties.

Novel fluorescent sensors L1–L3 based on triaryl 1H-imidazo[4,5-b]pyrazine have been synthesized through a new and simple route from inexpensive and readily available materials in one pot. They exhibited high selectivity for palladium detection (oxidation states of 0 and +2) based on the fluorescence quenching effect.

An efficient method for the construction of ketonitriles and α-aryl ketones by tert-butyl peroxybenzoate (TBPB) mediated direct alkylation of acetonitrile and alkanes with α,α-diaryl allylic alcohols has been developed. The reactions involve C(sp3)–H functionalization and radical addition/1,2-aryl migration processes under metal-free conditions.

An efficient I2 (20 mol %)/TBPB mediated oxidative formal [4 + 1] cycloaddition of N-tosylhydrazones with anilines via C-N/N-N bond formation and S-N cleavage has been developed. This protocol represents a simple, general, and efficient approach for the construction of 1,2,3-triazoles under metal-free and azide-free conditions by utilizing a catalytic amount of I2.

Dihydroartemisinin, formerly known as an antimalarial drug, is the main metabolite of the mother compound artemisinins, as well as of artemether and artesunate. It has been shown that the drug exhibits antischistosomal efficacy against Schistosoma japonicum. The purpose of the current study was to assess the in vivo effect of dihydroartemisinin against Schistosoma mansoni infection in mice. Drugs at a single oral dose of 300 mg/kg were given to mice to assess the efficacy against different developmental stages of the parasite; juvenile and adult S. mansoni were treated with single doses of dihydroarteminisin with different regimens (at 200, 300, 400 or 600 mg/kg) in the stage of drug sensitivity, and the dose-response relationship was assessed; and the effect of multiple doses (at 200, 300 or 400 mg/kg) on juvenile and adult S. mansoni was also observed. The results showed that a single oral dose (300 mg/kg) of dihydroartemisinin reduced total worm burdens by 13.8-82.1% and female worm burdens by 13-82.8%, and the greatest reductions were seen when treatment was given on day 21 post-infection, with total and female worm burden reductions of 82.1% and 82.8%. Administration of a single oral dose of dihydroartemisinin on day 21 post-infection with different drug dosage (at 200, 300, 400 or 600 mg/kg) reduced total worm burdens by 70.3-87.3% and female worm burdens by 73.5-92.4%, depending on dosage. Similar treatments given on day 49 post-infection reduced total worm burdens by 48.7-68.73% and female worm burdens by 63.25-94.6%. There was obvious dose-response relationship of dihydroartemisinin against the schistosomula and adult worms of S. mansoni observed. Administration with dihydroartemisinin at oral doses of 200, 300 and 400 mg/kg, given once on each of days 20-22 post-infection of three successive days, reduced total worm burdens by 88.5-90.1% and female worm burdens by 89.2-92.1%, depending on dosage. Similar treatments given once on each of days 48-50 post-infection reduced total worm burdens by 60-70.3% and female worm burdens by 77.5-94.9%. It is concluded that dihydroartemisinin exhibits in vivo activity against various developmental stages of S. mansoni, particularly the 21-day schistosomula, and there is obvious dose-response relationship of dihydroartemisinin against the schistosomula and adult worms of S. mansoni observed.

Artemether and artesunate, derivatives of the antimalarial artemisinin, as well as their main metabolite, dihydroartemisinin, all exhibit antischistosomal activities. The purpose of the current study was to compare the effects of artemether, artesunate and dihydroartemisinin administered orally at multiple doses or combination in treatment of mice infected with Schistosoma japonicum. We carried out experiments with mice, infected with 40 cercariae of S. japonicum, and treated with artemether, artesunate and dihydroartemisinin (all at a single dose of 300 mg/kg, and the dose of the mixed three drugs is also 300 mg/kg) at multiple doses or combination therapy on days 6-8 or 34-36 post-infection. Administration with artemether, artesunate or dihydroartemisinin for 3 successive days reduced total worm burdens by 79.5-86% (30.86 ± 4.98 of mean total worm burden in control), female worm burdens by 79.4-86.7% (11.29 ± 2.63 of mean female worm burden in control) (all P values0.01 vs. control), depending on different treatment protocols given on days 6-8 post-infection. However, no differences were seen between each treatment group (all P0.05). While the same treatment was given on days 34-36 post-infection, total worm burden reductions of 73.8-75.8% were achieved (29.44 ± 3.36 of mean total worm burden in control), which were significant when compared with the untreated control group (all P values0.01). In all different treatment groups, female worm reductions (ranging from 88.7% to 93.1%, while the mean female worm burden in control is 10.33 ± 1.80) were consistently higher than the total worm reductions, resulting always in significantly lower female worm burdens when compared to the corresponding control (all P values0.01). However, there were no significant differences found between each treatment group (all P values0.05). It is concluded that artemether, artesunate and dihydroartemisinin can be used to control schistosomiasis japonica, as a strategy to prevent S. japonicum infection. Administration with artemether, artesunate and dihydroartemisinin at multiple doses or in combined treatment damages both juvenile and adult S. japonicum, without statistically significant differences among the three drugs at the same dose.

A convenient method has been established for the chemoselective synthesis of polyarylated oxazoles from aromatic aldehydes and 2-cyano heteroarenes. The protocol presents a novel one-pot methodology for the synthesis of oxazole derivatives without any metal catalysts or extra oxidants. Photophysical test showed that the polyarylated oxazoles may serve as potential fluorescent materials with blue light-emitting properties.

Novel fluorescent sensors L1–L3 based on triaryl 1H-imidazo[4,5-b]pyrazine have been synthesized through a new and simple route from inexpensive and readily available materials in one pot. They exhibited high selectivity for palladium detection (oxidation states of 0 and +2) based on the fluorescence quenching effect.

Cyclic and acyclic alkyl and aryl ketones, esters, lactones, carbonates, amides, and formamides as well as lactams react with symmetric and non-symmetric α,α-diaryl allylic alcohols.

The formal [4 + 1] cycloaddition of tosylhydrazones with anilines proceeds via a C-N/N-N bond formation and a S-N cleavage.

The monoaryl allylalcohol 2-phenyl-but-3-en-2-ol is almost inert under the reaction conditions.

A novel radical phosphinylation of α,α-diaryl allylic alcohols with arylphosphine oxides was described for the direct preparation of α-aryl-β-phosphinylated carbonyl ketones in medium to good yields via 1,2-aryl migration. In this reaction, formation of new C(Ar)-C(sp(3)) and C(sp(3))-P bonds was observed.

Background Because there is little research on the effects of transplanted stem cells on neuronal metabolites in infarct areas, we transplanted human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) into cerebral ischemic rabbits and examined the neuronal metabolites. Results Rabbits (n = 40) were equally divided into sham, middle cerebral artery occlusion (MCAO), hUCB-MSC, and saline groups. The rabbit ischemic model was established by MCAO. The effects of hUCB-MSC transplantation were assessed by proton magnetic resonance spectroscopy (1H-MRS), neurological severity scores (NSSs), infarct area volume, neuronal density, and optical density (OD) of microtubule-associated protein 2 (MAP2)-positive cells. We also evaluated complete blood cell counts(CBCs) and serum biochemical parameters. NSSs in the hUCB-MSC group at 7 and 14 days after reperfusion were lower than in MCAO and saline groups (p p 1H-MRS revealed an elevation in the lactate (Lac)/creatine including phosphocreatine (Cr) ratio and a decrease in the N-acetylaspartate (NAA)/Cr and choline-containing phospholipids (Cho)/Cr ratios at 24 h after MCAO in the MCAO group (p p p Conclusions Transplanted hUCB-MSCs might ameliorate ischemic damage by influencing neuronal metabolites in the infarct area, providing additional evidence for neuroprotection by stem cells. No significant changes were observed in CBCs or serum biochemical parameters, suggesting that intravenous infusion of hUCB-MSCs is safe for rabbits in the short-term.

Organic light emitting diodes (OLED) with blue or white emission have been made from a new blue emitting material 9,10-bis(3'5'-diaryl)phenyl anthracene (JBEM). The two devices have the same structure except for a red dye doped in JBEM layer of the white device. The white device shows higher quantum efficiency and more than twice stability than that of the blue device. Mmaximum luminance of 14850cd/m 2 , quantum efficiency of 1.75% and a half lifetime of 2860h at initial luminance of 100cd/m 2 were achieved. This indicates that the doping is very important for improving the EL properties, particularly the stability. With comparison of a blue device from distyrylarylene derivatives, the blue device using JBEM shows 5 times better stability, indicating JBEM is a promising blue emitter.