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Alkaloids with a phenylhydrazone architecture are rarely found in nature. Four unusual phenylhydrazone alkaloids named talarohydrazones A–D (1–4) were isolated from the deep-sea cold seep derived fungus Talaromyces amestolkiaeHDN21-0307 using the one strain–many compounds (OSMAC) approach and MS/MS-based molecular networking (MN) combined with network annotation propagation (NAP) and the unsupervised substructure annotation method MS2LDA. Their structures were elucidated by spectroscopic data analysis, single-crystal X-ray diffraction, and quantum chemical calculations. Talarohydrazone A (1) possessed an unusual skeleton combining 2,4-pyridinedione and phenylhydrazone. Talarohydrazone B (2) represents the first natural phenylhydrazone-bearing azadophilone. Bioactivity evaluation revealed that compound 1exhibited cytotoxic activity against NCI-H446 cells with an IC50value of 4.1 μM. In addition, compound 1displayed weak antibacterial activity toward Staphylococcus aureuswith an MIC value of 32 μg/mL.

Creating a perfect catalyst to operate enzyme-like chiral recognition has been a long-sought aim. A challenging example in this context is constructing acyclic all-carbon quaternary stereogenic centers by transition metal-catalyzed enantioselective C–H activation. We now report highly enantioselective iridium-catalyzed primary C–H borylation of α-all-carbon substituted 2,2-dimethyl amides enabled by a tailor-made chiral bidentate boryl ligand (CBL). The success of the current transformation is attributed to the CBL/iridium catalyst, which has a confined chiral pocket. This protocol provides a diverse array of acyclic all-carbon quaternary stereocenters with excellent enantiocontrol and distinct structural features. Computational study reveals that steric hindrance of CBLcould regulate the type of dominant orbital interaction between the catalyst and substrate, which is crucial to conferring high chiral induction.

• Ti 3 C 2 T x MXenes intercalated with C 60 assisted by γ-cyclodextrin for EMI shielding. • Layer spacing increased by C 60 would cause more absorption of EMWs. • Antioxidative C 60 would promote the durability of EMI SE. • The EMI shielding films exhibit excellent mechanical robustness and flexibility. Ti 3 C 2 T x MXenes with excellent metallic conductivity and flexibility have shown a promising prospect as electromagnetic interference (EMI) shielding materials. Ultrathin, hierarchical hybrid films were fabricated by using C 60 intercalating Ti 3 C 2 T x MXenes with the assistance of water-soluble γ -cyclodextrin (CD). The C 60 /CD complex was obtained by high-speed vibration milling using hydrophilic CD as dispersing agent. After thermal annealing treatment, the obtained hybrid film exhibited excellent EMI shielding (53.52±0.43 dB), hydrophobicity (water contact angle: 93.7°) and mechanical stability (over 0.9 million bending times). Taking advantage of the antioxidant of C 60 , the chemical durability of Ti 3 C 2 T x MXenes based hybrid films was also improved as expected. These results indicate that the well-designed hierarchical hybrid films with the intercalation of C 60 have promising potential for high-performance EMI shielding applications. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of the supplementation of branched-chain amino acids (BCAAs) at different ratios in protein restriction diets on lipid metabolism in a finishing pig model. The BCAA supplementation (leucine/isoleucine/valine = 2:1:1 and 2:1:2) ameliorated the poor growth performance and carcass characteristics, particularly high fat mass caused by a protein-restricted diet. Serum adiponectin increased while leptin decreased in BCAA diets in comparison to the 12% CP group. BCAA supplementation also increased the low-protein expression of AMPK and SIRT1 caused by protein restriction. The mRNA and protein levels of peroxisome proliferation-activated receptor-γ (PPARγ) and acetyl-CoA carboxylase (ACC) were highest in the protein-restricted group and lowered in the 2:1:1 or 2:1:2 group. In conclusion, BCAAs supplemented in an adequate ratio range of 2:1:1 to 2:1:2 (2:1:2 is recommended) in reduced protein diets could modulate lipid metabolism by accelerating the secretion of adipokines and fatty acid oxidation.

We herein report an iridium-catalyzed enantioselective α-C(sp3)–H borylation of a wide range of azacycles. The combination of an iridium precursor and a chiral bidentate boryl ligand has been shown to effectively differentiate enantiotropic methylene C–H bonds from a single carbon center, affording a variety of synthetically useful azacycles from readily available starting materials with good to excellent enantioselectivities.

Herein, the effect of recrystallization on the bainite transformation and mechanical properties of CH steel were investigated using SEM, TEM, EBSD, dilatometry, and tensile testing machine. First, precipitation was introduced to hinder recrystallization by batch annealing. Subsequently, the competitive relationship between austenite transformation and recrystallization was revealed using different annealing processes. Finally, the effect of recrystallization on bainite transformation was analyzed, mainly including bainite morphology, fraction, transformation rate, bainite nucleation rate of untransformed austenite and austenite-bainite orientation relationship, as well as the effect on the mechanical properties. After batch annealing, a large amount of cementite and nanoscale (Nb, Ti)C precipitated in the hot-rolled sheet, the austenite transformation start temperature (Ac1) and the pearlite to austenite transformation end temperature (Ac1f)of the cold-rolled sheet increased, and the austenite transformation end temperature (Ac3) of the cold-rolled sheet decreased, and the austenite transformation process accelerated. The microstructure of annealed sheets is consisted of ferrite, granular bainite, martensite, and a small fraction of retained austenite. Carbide hindered the recrystallization process during the annealing process, resulting in significant refining of the grains. The lower degree of recrystallization promoted bainite transformation, providing more nucleation sites, higher grain boundary and autocatalytic nucleation activation energy, improving bainite's fraction and transformation rate. The bainitic ferrite was mainly lathy in the recrystallized zone and polygonal in the non-recrystallized zone. Both a K-S and an N-W relationship between retained austenite and bainite, while the N-W relationship in the non-recrystallized zone was relatively higher. Without severe loss of plasticity, hindering recrystallization increased the dislocation, grain refinement, and precipitation strengthening values of the samples, and the strength significantly improved. However, with the increase of annealing temperature, recrystallization fraction increased gradually, and the increase in strength became less noticeable.