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The selective hydrogenation of halogenated nitroaromatic compounds is of great importance in the fine chemical industry. However, the hydrogenation reactions in commonly utilized batch reactors suffer from the undesired dehalogenation, resulting in higher requirement for subsequent separation processes and severe corrosion to industrial fatalities. In this work, a H-flow system with the micropacked bed reactor was developed for the selective hydrogenation of halogenated nitroaromatic compounds and the reduction of 3,4-dichloronitrobenzene was selected as the model reaction. With the optimal hydrogenation conditions, the yield of 3,4-dichloroaniline was obtained as high as 99.8% under mild conditions. With this strategy this flow system was successfully employed to the reduction of other chlorinated nitroaromatics also demonstrating low dehalogenation. The H-flow system enables negligible dehalogenation and remarkable yield of target product with higher efficiency and lower energy cost compared with the batch reactor.

Lifelong premature ejaculation (PE) is one of the most prevalent male sexual dysfunctions. It is still not well known about the possible neural mechanisms of lifelong PE. This study tried to investigate the abnormal characteristics of brain functional networks of lifelong PE and to assess relationships of PE-related functional abnormalities with clinical symptoms. Functional magnetic resonance imaging (fMRI) data and clinical symptoms were collected from 45 lifelong PE patients and 37 healthy controls (HCs) since 2016, including disease and sexual life history, intravaginal ejaculatory latency time measured by stopwatch and other scales. The degree centrality (DC) approach were applied to distinguish altered brain functions between the two groups (p

A study was carried out on the behavior of monomeric germylenes derived from pyridine-containing diols in reactions with diphenylphosphoryl azide and 9,10-phenanthrenequinone. It was found that the germanium atom increases its oxidation state to 4+ in these reactions. The structure of the product of the reaction with 9,10-phenanthrenequinone was confirmed by X-ray structural analysis, which showed a transannular germanium-nitrogen interaction in this product.

New 1,3,6,2-dioxazaborocanes R1N(CHR3CR4R2O)(CHR6CHR5O)BX (1–11, X = Ph, 4-MeC6H4, Me; R1 = Me, PhCH2; R2, R3, R4, R5, R6 = H, Ph) were synthesized by the reactions of aryl- or methylboronic acids with dialkanolamines. The treatment of (Me2NCH2CH2O)3B (15) with MeN(CH2CH2OH)(CH2CPh2OH) afforded 2-[2-(dime-thylamino)ethoxy]-1,3,6,2-dioxazaborocane (12). 2-Fluoro-1,3,6,2-dioxazaborocanes R1N(CHR3CHR2O)(CH2CH2O)BF (13: R1 = PhCH2, R2 = R3 = H; 14: R1 = Me, R2 = R3 = Ph, threo) were synthesized by the reaction of bis(trimethylsilyl) ethers of the corresponding dialkanolamines with BF3·Et2O. The new borocanes can be used for the synthesis of the corre-sponding germanium derivatives PhCH2N(CH2CH2O)2GeX2 (16, X = OEt; 17, X = Cl), as exemplified by the reaction of compound 6. The structures of erythro-MeN(CH2CH2O)(CHPhCHPhO)BPh (3), threo-MeN(CH2CH2O)(CHPhCHPhO)BPh (4), erythro-MeN(CH2CH2O)(CHPhCHPhO)B(4-MeC6H4) (8), and PhCH2N(CH2CH2O)2BF (13) were established by X-ray diffraction. The coordination polyhedra of the boron atoms in these complexes can be described as distorted tetrahedra. The boron-nitrogen distances (1.705(7)–1.723(3) A) provide unambiguous evidence for the presence of the B←N transannular interaction in these compounds. The structures of the resulting borocanes containing phenyl substituents at the carbon atoms of the ocane skeleton were studied by NMR spectroscopy and quantum chemical density functional theory calculations.

The RNA interference (RNAi) plays a critical role in gene regulation in a variety of eukaryotic organisms. However, the role of RNAi remains largely unclear in plant pathogenic fungi. In this study, we explored the roles of core components of the RNAi pathway in Fusarium graminearum, the major causal agent of wheat head blight. Our results demonstrated that the hairpin RNA (hpRNA) can efficiently silence the expression level of target gene and the argonaute protein FgAgo1 and dicer protein FgDicer2 are important in this silencing process. RNAi machinery was not involved in growth, abiotic stress and pathogenesis in F. graminearum under tested conditions. We firstly applied high-throughput sequencing technology to elucidate small RNA (17–40 nucleotides) (sRNA) transcriptome in F. graminearum and found that a total of forty-nine micro-like-RNA (milRNA) candidates were identified in the wild-type and ∆FgDICER2 and twenty-four of them were FgDicer2-dependent. Fg-milRNA-4 negatively regulated expression of its target gene. Taken together, our results indicated that the hpRNA-induced gene silencing was a valuable genetic tool for exploring gene function in F. graminearum. FgAgo1 and FgDicer2 proteins played a critical role in the hpRNA mediated gene silencing process. In addition, FgDicer2 was involved in sRNA transcription and milRNA generation in this fungus.

Designer transcription-activator like effectors (TALEs) is a promising technology and made it possible to edit genomes with higher specificity. Such specific engineering and gene regulation technologies are also being developed using RNA-binding proteins like PUFs and PPRs. The main feature of TALEs, PUFs and PPRs is their repetitive DNA/RNA-binding domains which have single nucleotide binding specificity. Available kits today allow researchers to assemble these repetitive domains in any combination they desire when generating TALEs for gene targeting and editing. However, PCR amplifications of such repetitive DNAs are highly problematic as these mostly fail, generating undesired artifact products or deletions. Here we describe the molecular mechanisms leading to these artifacts. We tested our models also in plasmid templates containing one copy versus two copies of GFP-coding sequence arranged as either direct or inverted repeats. Some limited solutions in amplifying repetitive DNA regions are described.