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Carbonyl addition serves as a strategically straightforward and versatile approach for synthesizing alcohols, which are often encountered within bioactive molecules. Herein, we present a ligand‐free, nickel‐catalyzed carbonyl addition process using organoboron reagents. This method enables efficient arylation of readily available ketones or aldehydes, affording a variety of tertiary and secondary alcohols. Key highlights of this protocol include the obviation of external ligands and the tolerance to many functional groups and heterocycles, thereby enhancing its practicality and utility in synthetic organic chemistry. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Transition‐metal‐catalyzed asymmetric alkylation of aldehydes represents a straightforward strategy for the synthesis of chiral secondary alcohols. However, efficient methods using organoborons as coupling reagents are rare. Herein, we report a highly enantioselective nickel‐catalyzed alkylation reaction of aldehydes, using readily available alkylborons as nucleophiles. A wide variety of chiral secondary alcohols were prepared from commercially available aldehydes with high yields. The key to the excellent enantioselectivity and chemoselectivity was the employment of a bulky C2‐symmetric chiral NHC ligand. This protocol features excellent enantiocontrol, mild conditions, and good functional group compatibility. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Transition‐metal‐catalyzed asymmetric alkylation of aldehydes represents a straightforward strategy for the synthesis of chiral secondary alcohols. However, efficient methods using organoborons as coupling reagents are rare. Herein, we report a highly enantioselective nickel‐catalyzed alkylation reaction of aldehydes, using readily available alkylborons as nucleophiles. A wide variety of chiral secondary alcohols were prepared from commercially available aldehydes with high yields. The key to the excellent enantioselectivity and chemoselectivity was the employment of a bulky C2‐symmetric chiral NHC ligand. This protocol features excellent enantiocontrol, mild conditions, and good functional group compatibility. [ABSTRACT FROM AUTHOR]

Understanding the mechanical response characteristics and determining the optimized process conditions is critical to mitigate crystal impacts during resonant acoustic mixing (RAM). Therefore, high‐melting explosive (HMX) crystal collisions with container walls under different RAM accelerations were investigated through simulations and experiments. The HMX crystal damages after RAM were assessed using microscopic imaging, small‐angle X‐ray scattering, and Brunauer–Emmett–Teller tests. Results show that crystal fractures observed in steel containers can be prevented by using low‐modulus polytetrafluoroethylene containers. Rough containers reduce internal damage but increase surface abrasion. Lower RAM accelerations, shorter RAM durations, and low‐modulus containers can mitigate HMX crystal damage. [ABSTRACT FROM AUTHOR]

Summary: This study investigated the compositional profile and inhibitory effect of brown sugar polyphenols (BSPs) on porcine pancreatic α‐amylase (PPA) and Baker's yeast α‐glucosidase (BYG) activities. The HPLC‐ESI‐MS (high‐performance liquid chromatography‐electrospray ionisation‐mass spectrometry) analysis showed that BSPs comprised of four hydroxybenzoic acids including protocatechuic, p‐hydroxybenzoic, vanillic and syringic acids (PA, PHBA, VA and SA, respectively) and three hydroxycinnamic acids including chlorogenic, p‐coumaric and ferulic acids (CHA, PCA and FA, respectively), where CHA (29.24%) and SA (31.31%) were the main BSPs. The enzyme inhibition analysis expressed as IC50 values (except PA and VA) showed that CHA, PCA and FA exhibited higher PPA and BYG inhibitory activities than PHBA and SA, following the order of CHA > PCA > FA > PHBA > SA. Moreover, the BSPs showed better inhibitory activities against BYG than PPA. The inhibition mechanism analysis through inhibitory kinetics, fluorescence quenching, differential scanning calorimetry and molecular docking demonstrated that the BSPs inhibited the enzymes by binding with them mainly via hydrogen bonds. The results suggested that BSPs could be natural inhibitors of PPA and BYG. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed C−H insertion reaction is a straightforward strategy to realize the direct functionalization of electric‐rich (hetero)arenes. The known methods generally require metal catalysts chelating with well‐defined ligands and the use of additives; a simple and practical catalytic system is still needed. We herein report a ligand‐ and additive‐free, CuCl2‐catalyzed highly selective para‐C−H carbene insertion of aniline derivatives using α‐aryl‐α‐diazo esters. A diverse array of 1,1‐diarylacetates were obtained in high yields with excellent chemo‐ and regioselectivity. [ABSTRACT FROM AUTHOR]

Due to their high prevalence and incidence, diabetes and atherosclerosis are increasingly becoming global public health concerns. Atherosclerosis is one of the leading causes of morbidity and disability in type 1 and/or type 2 diabetes patients. Atherosclerosis risk in diabetic patients is obviously higher than that of non-diabetic individuals. Diabetes-related glycolipid metabolism disorder has been shown to play a central role in atherosclerosis development and progression. Hyperglycemia and dyslipidemia increase the risks for atherosclerosis and plaque necrosis through multiple signaling pathways, such as a prolonged increase in reactive oxygen species (ROS) and inflammatory factors in cardiovascular cells. Notwithstanding the great advances in the understanding of the pathologies of diabetes-accelerated atherosclerosis, the current medical treatments for diabetic atherosclerosis hold undesirable side effects. Therefore, there is an urgent demand to identify novel therapeutic targets or alternative strategies to prevent or treat diabetic atherosclerosis. Burgeoning evidence suggests that plant and herbal medicines are closely linked with healthy benefits for diabetic complications, including diabetic atherosclerosis. In this review, we will overview the utilization of plant and herbal medicines for the treatment of diabetes-accelerated atherosclerosis. Furthermore, the underlying mechanisms of the ethnopharmacological therapeutic potentials against diabetic atherosclerosis are gathered and reviewed. It is foreseeable that the natural constituents from medicinal plants might be a new hope for the treatment of diabetes-accelerated atherosclerosis. [ABSTRACT FROM AUTHOR]