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A Rh‐catalyzed asymmetric hydroboration of dialkyl ketone‐derived silyl enol ethers with HBpin has been developed using a commercially available catalyst and ligand ([RhCl (cod)]2 and MeO‐BIBOP). A variety of silyl enol ethers undergo this asymmetric transformation, providing the corresponding products with high enantioselectivity (up to 97 : 3 % er). In addition, the utility of this protocol is demonstrated by the versatile transformation of chiral borylether products to a range of valuable derivatives. [ABSTRACT FROM AUTHOR]

Controlling the optical activity of halide perovskite materials through modulation of the coordination configurations of the metal ions is important. Herein, a novel manganese‐based halide, specifically diaquatetrakis(methyldiphenylphosphine oxide)manganese(II) tetrachloridomanganate(II), [Mn(C13H13OP)4(H2O)2][MnCl4] or [Mn(MDPPO)4(H2O)2][MnCl4] (MDPPO is methyldiphenylphosphine oxide), was synthesized through the solvothermal reaction of MnCl2 with the neutral molecule MDPPO. In this compound, [Mn(MDPPO)4(H2O)2]2+ acts as the cation, while [MnCl4]2− serves as the anion, enabling the co‐existence of tetrahedral and octahedral structures within the same system. Remarkably, the compound exhibits efficient red‐light emission at 662 nm, distinct from the green‐light emission typically observed in MnX4‐based halides. Theoretical calculations show that the red emission comes from the charge transfer from the MDPPO to the Mn2+ of [MnCl4]2−. This work provides a new perspective for the design and synthesis of red‐light‐emitting manganese‐based halides with unique structures. [ABSTRACT FROM AUTHOR]

Drought stress is a common abiotic stress, and Lupinus polyphyllus presents strong adaptability, but its drought resistance mechanism has not been explored. This study used PEG-6000 to simulate drought stress, and the H2O2 content, O2− generation rate and MDA content were determined. Transcriptome sequencing and untargeted metabolome analyses were also carried out on an Iceland germplasm and American B germplasm under different drought stress durations. The results showed that the gene regulation range in the American B germplasm was greater, whether genes were upregulated or downregulated. And the number of genes in the American B germplasm was higher than that in the Iceland germplasm. Additionally, the Iceland germplasm produced less peroxide under PEG stress than the Iceland germplasm. The Iceland germplasm was more stable than the American B germplasm under PEG stress, which can be shown in two aspects: peroxide content and gene regulation quantity. Joint transcriptomics and metabolomics analysis showed that genes and metabolites related to secondary and carbon metabolism were mainly involved in the response of Lupinus polyphyllus to PEG-simulated drought stress. The metabolites mainly included phenylalanine, tyrosine, trans-2-hydroxycinnamate, starch synthase, 1,4-alpha glucan branching enzyme and glycogen phosphorylase, and genes mainly included COMT, F5H, REF1, CAD, UGT72E and TPS. These results provided genetic resources and a theoretical basis for further molecular breeding of Lupinus polyphyllus. [ABSTRACT FROM AUTHOR]

Catalytic asymmetric hydroboration of alkenes is a powerful tool for the synthesis of natural products, agrochemicals, and pharmaceuticals via the versatile transformations of chiral alkyl boronic esters. However, the scope of available alkenes is limited to styrenes, activated alkenes, and compounds with directing groups. The catalytic enantioselective hydroboration of heteroatom‐substituted alkenes is rarely explored and those catalyzed by earth‐abundant metals are yet to be reported. Herein, we report a cobalt‐catalyzed asymmetric hydroboration of ketone‐derived silyl enol ethers and provide a convenient approach to access valuable enantiopure β‐hydroxy boronic esters. This protocol features mild reaction conditions, a broad substrate scope, and excellent enantioselectivities (up to 99 % ee). This approach was applied in the successful synthesis of salmeterol and albuterol, demonstrating its potential to streamline complex molecule synthesis. [ABSTRACT FROM AUTHOR]

A new efficient method for the synthesis of a high ratio of E -alkenes from E / Z mixtures of alkenes with B2 pin2 in the presence of a rhodium catalyst is described. This reaction features mild reaction conditions, broad functional group tolerance, and highly great application potential. [ABSTRACT FROM AUTHOR]

Aquatic viral diseases pose significant threats to aquaculture, necessitating the exploration of effective preventive measures. In this study, we evaluated the antiviral potential of Cinnamomum cassia (L.) D. Don (CCD) aqueous extracts against Micropterus salmoides rhabdovirus (MSRV) in largemouth bass aquaculture. Initially, twelve plant extracts were screened for antiviral activity against MSRV, revealing that CCD extracts at 100 mg/L concentration significantly inhibited MSRV proliferation in vitro. Further dose-response analysis revealed a concentration-dependent antiviral effect of CCD extracts, with higher concentrations demonstrating increased efficacy against MSRV. Subsequent investigations focused on the protective effects of CCD extracts on MSRV-infected cells. At a concentration of 63 mg/L, CCD extracts significantly reduced MSRV titers, preventing the onset of cytopathic effects (CPE) in cells. Fluorescence and transmission electron microscopy further illustrated the protective effects of CCD extracts on cellular morphology. MSRV-infected cells treated with CCD exhibited preserved cell morphology akin to normal cells, contrasting with the typical apoptotic features observed in untreated infected cells. Additionally, dietary supplementation of CCD extracts in largemouth bass demonstrated notable benefits. Fish fed with CCD extracts exhibited increased survival rates when infected with MSRV, with a 26 % higher survival rate compared to the virus-only group. Furthermore, CCD supplementation enhanced the expression of interferon-gamma (IFNγ), indicating improved immune responses in largemouth bass. Moreover, immersion of CCD extracts in water showed partial inhibition of horizontal MSRV transmission, effectively reducing viral spread and mitigating disease risks in fish populations. These findings highlight the potential of CCD aqueous extracts as feed additives for combating MSRV in aquaculture, showcasing their promising application prospects in disease prevention and control strategies. • CCD aqueous extracts exhibit potent antiviral effects against MSRV. • Feeding CCD enhances largemouth bass survival and immune response. • Potential for CCD as a natural remedy and feed additive in MSRV control. [ABSTRACT FROM AUTHOR]

The asymmetric hydroboration of alkenes has proven to be among the most powerful methods for the synthesis of chiral boron compounds. This protocol is well suitable for activated alkenes such as vinylarenes and alkenes bearing directing groups. However, the catalytic enantioselective hydroboration of O-substituted alkenes has remained unprecedented. Here we report a Rh-catalyzed enantioselective hydroboration of silyl enol ethers (SEEs) that utilizes two new chiral phosphine ligands we developed. This approach features mild reaction conditions and a broad substrate scope as well as excellent functional group tolerance, and enables highly efficient preparation of synthetically valuable chiral borylethers.

We develop herein an efficient rhodium-catalyzed remote isomerization of aromatic and aliphatic alkenyl alcohols into ketones. This catalytic process, with a commercially available catalyst and ligand ([RhCl(cod)] 2 and Xantphos), features high efficiency, low catalyst loading, good functional group tolerance, a broad substrate scope, and no (sub)stoichiometric additive. Preliminary mechanistic studies suggest that this transformation involves an iterative dissociative β-hydride elimination-migration insertion process.