Electrochemical oxidative site-selective direct C-H activation of tanshinone IIA.

Natural products play a pivotal role in the advancement of state-of-the-art pharmaceuticals. To augment their therapeutic efficacy, structural modifications of these compounds are routinely performed. In this study, we introduce an efficient and environmentally benign electrochemical oxidative method for site-selective direct C-H activation of tanshinone IIA under metal-free, oxidant-free, and base-free conditions.

Electrochemical oxidative selective halogenation of pyrazolones for the synthesis of 4-halopyrazolones.

An efficient and environmentally friendly electrochemical oxidative selective halogenation of pyrazolones has been developed under conditions free of metals, external oxidants, and external supporting electrolytes. The reaction demonstrates good functional group tolerance and maintains high efficiency in large-scale synthesis, yielding moderate to excellent yields of the desired 4-halopyrazolones. This method provides a green and convenient route for the direct installation of a halogen moiety into bioactive pyrazolone derivatives, which can be utilized in a myriad of applications.

Electrochemical oxidative radical cascade cyclization of dienes and diselenides towards the synthesis of seleno-benzazepines.

Selenium-containing compounds are important scaffolds owing to their value in medicinal chemistry, biochemistry and material chemistry. Herein, we report an electrochemical approach to access seleno-benzazepines through an oxidative radical cascade cyclization of dienes with diselenides under metal-free, external oxidant-free and base-free conditions. In a simple undivided cell, various dienes and diselenides were suitable for this transformation, generating the desired products in up to 84% yields.

Rapid Formation of Intramolecular Disulfide Bridges using Light: An Efficient Method to Control the Conformation and Function of Bioactive Peptides.

Disulfide bonds are widely found in natural peptides and play a pivotal role in stabilizing their secondary structures, which are highly associated with their biological functions. Herein, we introduce a light-mediated strategy to effectively control the formation of disulfides. Our strategy is based on 2-nitroveratryl (Nv), a widely used photolabile motif, which serves both as a photocaging group and an oxidant (after photolysis).

Framework to Guide Health Professions Faculty Towards Increased Scholarship: Recommendations from the ASAHP Research, Discovery & Innovation Committee.

The Research, Discovery, and Innovation Publications (RDI-P) Task Force met from October 2020 to March 2022 to discuss ways in which the Association of Schools Advancing Health Professions (ASAHP) can help to guide institutional leaders to assign faculty effort and resources to enable success with the scholarship mission. The purpose of this White Paper is to propose a guiding framework for institutional leaders to determine their faculty's individual or team scholarly goals, assign appropriate percent efforts (funded/unfunded), and guide an overall faculty mix that balances required teaching loads with scholarly activities. The Task Force identified seven modifiable factors that can influence workload allocation for scholarship: 1.

Electrochemical Oxidative Cross-Coupling of Enaminones and Thiophenols to Construct C-S Bonds.

An electrochemical oxidative C(sp)-H sulfuration has been developed. Various enaminones and thiophenols were compatible, generating the desired alkenyl sulfur compounds in up to 87 % yield. This transformation proceeded smoothly under mild reaction conditions without external oxidant and transition-metal catalyst.

A new role for host annexin A2 in establishing bacterial adhesion to vascular endothelial cells: lines of evidence from atomic force microscopy and an in vivo study.

Understanding bacterial adhesion is challenging and critical to our understanding of the initial stages of the pathogenesis of endovascular bacterial infections. The vascular endothelial cell (EC) is the main target of Rickettsia, an obligately intracellular bacterium that causes serious systemic disease in humans and animals. But the mechanism(s) underlying bacterial adherence to ECs under shear stress from flowing blood prior to activation are unknown for any bacteria.

Copper-catalyzed selective radical-radical cross-coupling for C-S bond formation: an access to α-alkylthionitriles.

A new protocol for C-S bond formation was developed by selective cross-coupling between a thiyl radical and an isobutyronitrile radical. Using this strategy, a series of valuable α-alkylthionitrile derivatives were synthesized from basic starting materials. Preliminary mechanistic investigation was performed by EPR and XAFS, revealing that the transient thiyl radical could be stabilized by a copper catalyst to a persistent one.

Palladium/Copper-Catalyzed Oxidative Coupling of Arylboronic Acids with Isocyanides: Selective Routes to Amides and Diaryl Ketones.

An efficient and alternative oxidative cross-coupling strategy starting from arylboronic acids and isocyanides for the selective synthesis of amides and diaryl ketones with palladium/copper catalysis is developed. Various substituted benzamides and benzophenones could be obtained in good yields. The reaction represents an efficient and alternative strategy for the synthesis of carbonyl compounds.

Oxidative Alkane C-H Alkoxycarbonylation.

Directly utilizing a chemical feedstock to construct valuable compounds is an attractive prospect in organic synthesis. In particular, the combination of C(sp(3) )-H activation and oxidative carbonylation involving alkanes and CO gas is a promising and efficient method to synthesize carbonyl derivatives. However, due to the high C-H bond dissociation energy and low polarity of unactivated alkanes, the carbonylation of unactivated C(sp(3) )-H bonds still remains a great challenge.

Speech tasks and interrater reliability in perceptual voice evaluation.

Objective/hypothesis: The optimal selection of speech task is essential for more reliable perceptual ratings and a better understanding of the perceptual qualities of pathologic voices. Nevertheless, researchers have rarely explored this issue using the GRBAS scale. This study investigates the effect of speech task selection on interrater reliability during perceptual voice assessment.

Efficacy of intensive phonatory-respiratory treatment (LSVT) for presbyphonia: two case reports.

Objectives: Research evidence has shown that neither traditional voice therapy nor surgery was efficacious in managing age-related dysphonia, specifically for more severe cases with pronounced fold atrophy or larger glottal gaps. The purpose of this study was to examine the efficacy of intensive respiratory-phonatory treatment (Lee Silverman voice treatment [LSVT]) for glottal incompetence associated with presbyphonia.

Study Design: Nonrandomized prospective study.