An enantioselective synthesis of β‐chiral amides through asymmetric and redox‐neutral hydroamidation of enals is reported. In this reaction, a chiral N‐heterocyclic carbene (NHC) catalyst reacts with enals to gene...
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An enantioselective synthesis of β‐chiral amides through asymmetric and redox‐neutral hydroamidation of enals is reported. In this reaction, a chiral N‐heterocyclic carbene (NHC) catalyst reacts with enals to generate the homoenolate intermediate. Upon highly enantioselective β‐protonation through proton‐shuttle catalysis, the resulting azolium intermediate reacts with imidazole to yield the key β‐chiral acyl species. This transient intermediate provides access to diversified β‐chiral carbonyl derivatives, such as amides, hydrazides, acids, esters, and thioesters. In particular, β‐chiral amides can be prepared in excellent yield and ee (40 chiral amides, up to 95 % yield and 99 % ee ). This modular strategy overcomes the challenge of disruption of the highly selective proton‐shuttling process by basic amines.
We determined the complete mitochondrial genome ofMetapenaeopsis dalei(Rathbun, 1902), which is collected from East China Sea (124°E and 33.5°N). Total mitochondrial genome length ofM. daleiwas 15 939 bp, in...
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We determined the complete mitochondrial genome ofMetapenaeopsis dalei(Rathbun, 1902), which is collected from East China Sea (124°E and 33.5°N). Total mitochondrial genome length ofM. daleiwas 15 939 bp, in which 13 proteins, two ribosomal RNAs, 22 transfer RNAs and a putative control region were encoded. The gene arrangement ofM. daleiwas well conserved with nine known Penaeidae mitochondrial genomes fromCOX1totRNATyr. The protein-coding genes started with ATN except forCOX1in which ACG is used. Four genes (COX2, COX3, ND3andND5) exhibited an incomplete stop codon. Nucleotide sequence identity ofM. daleimitochondrial genome to those of nine Penaeidae species ranged from 78% to 80%. Based on the COI region,M. daleiis most closely related toPenaeus notialis.
The Escherichia coli(E. coli) isGram negative bacteria, that normally live in the digestive tracts of humans and animals, can cause bloody diarrhea, severe anemia or kidney falureand other illnesses which can lead to ...
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The Escherichia coli(E. coli) isGram negative bacteria, that normally live in the digestive tracts of humans and animals, can cause bloody diarrhea, severe anemia or kidney falureand other illnesses which can lead to *** therapy with antibiotic cause bacteria resistant. So, an alternative method is needed, one of them is Photodynamic therapy (PDT).This research aims to investigate antimicrobial photodynamic effects of the light emitting diode (LED) activated bymagnetic fields 1.8 mT irradiation to bacteria viability . To determine the antimicrobial effect of treatments, three measurements of bacterial colony growth (in %) were carried out. Three measurements groups as follow: Groups I to measurements the effects of LED irradiation by varying wavelength (469nm, 541 nm and 626 nm);Groups II to measurements effects of magnetic fields 1.8 mT to antimicrobial efficacy;Groups III to determine the effects and efficacy of LED 541 nm and magnetic fields irradiation with varying LED intensity (0.62, 2.50, 6.27, and 8.21) mW/cm2 and time irradiation (20, 30, 40, 50) minutes, respectively. The suspension was planted on sterile media and incubated at a temperature of 37°C for 24 hours. After incubation, the number of colony-forming units per milliliter (CFU/ml) was determined. The results were analyzed by analysis of variance (ANOVA) and the Tukey test. A P value =0.05 was considered to indicate a statistically significant difference. The LED treatment group 469 nm, 541 nm and 626 nm resulted in statistically significant decrease of CFU (p<0.05) compared to each other. The LED 541 nm treatment group with magnetic fields resulted significantly differ with treatment group without magnetic fields. The LED 541 nm treatment with magnetic fields 1.8 mT at various light intensity and time irradiation resulted significantly differ each other (p < 0.05). LED irradiation with intensity 6.27 mW/cm2 and time irradiation 50 minutes (energy dose 18.81 J/cm
Induction of neural stem/progenitor cells (NSPCs) and establishment of neural network are important issues on neural engineering. In this work, a platform was designed to control and evaluate the differentiation of NS...
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Induction of neural stem/progenitor cells (NSPCs) and establishment of neural network are important issues on neural engineering. In this work, a platform was designed to control and evaluate the differentiation of NSPCs, neurite direction, and to promote the neurite outgrowth. Polyelectrolyte multilayer (PEM) films provide surface properties by and have been used to regulate NSPCs differentiation in our previous study. Herein, a culture platform composed of SU-8 microchannel and PEM films was designed to achieve the goal of promoting NSPCs differentiation and to evaluate the effect of PEM films on the guidance of neural network formation. In this culture platform, NSPCs were induced into functional neurons, and neural network formation was accomplished on ITO glass-PEM films successfully.
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