Hemin-Catalyzed Oxidative Phenol-Hydrazone [3+3] Cycloaddition Enables Rapid Construction of 1,3,4-Oxadiazines

Electrochemical [3+3] Annulation of Phenol and Hydrazone: Synthesis of 1,3,4-Oxadiazines

A novel [3+3] cyclization reaction between phenol and hydrazone was successfully developed under electrochemically driven conditions. This reaction provided access to a diverse array of 1,3,4-oxadiazinane compounds in consistently high yields, reaching up to 87%. Notably, the reaction exhibited remarkable tolerance toward a broad spectrum of both phenol and hydrazone substrates, underscoring its versatility. Moreover, the protocol distinguished itself by its exceptional atom and step economy, facilitating the efficient construction of functionalized 1,3,4-oxadiazines. The synthetic utility of this approach was further exemplified by its scalability, as demonstrated by gram-scale reactions, and its broad substrate scope.

Catalytic Atroposelective Electrophilic Amination of Indoles

Reported here is the first catalytic atroposelective electrophilic amination of indoles, which delivers functionalized atropochiral N-sulfonyl-3-arylaminoindoles with excellent optical purity. This reaction was furnished by 1,6-nucleophilic addition to p-quinone diimines. Control experiments suggest an ionic mechanism that differs from the radical addition pathway commonly proposed for 1,6-addition to quinones. The origin of 1,6-addition selectivity was investigated through computational studies. Preliminary studies show that the obtained 3-aminoindoles atropisomers exhibit anticancer activities. This method is valuable with respect to enlarging the toolbox for atropochiral amine derivatives.

Recent advances in catalytic oxidative reactions of phenols and naphthalenols

This critical review aims to provide an overview of oxidative phenol and naphthalenol transformations in nature and synthetic chemistry.

Particulate matter exposure is highly correlated to pediatric asthma exacerbation

Asthma is a heterogeneous disease in which environmental factors play an important role, and the effect of particulate matter (PM) on the occurrence and severity of asthma is drawing more attention. This study aims to identify the correlation between PM and pediatric asthma exacerbation and explore the potential mechanisms. The asthma visits data (N = 16,779,739) in a university-based tertiary children’s hospital from January 2013 to December 2017 were collected, and the relationship between asthma visits and local PM concentration was analyzed. For further study, we established a house dust mite (HDM)-induced allergic airway inflammation model with PM intervention. We detected a correlation between PM concentration and pediatric asthma visits, especially in children under 6 years old. The in vivo data showed that PM aggravated HDM-induced airway inflammation, and IL-33 neutralizing antibody exerted a protective role. Our study suggests that PM is a risk factor in promoting pediatric asthma exacerbation, in which IL-33 might be a promising target.