Organoselenium-Catalyzed C2,3-Diarylation of N-H Indoles.

An organoselenium-catalyzed C2,3-diarylation of unprotected N-H indoles with electron-rich aromatics has been developed. This one-pot multicomponent tandem cross-dehydrogenation coupling reaction allows for the incorporation of two different aromatic groups to indoles. More importantly, this approach offers significant advantages, including a high atom and step economy, eliminating the need for prepreparation of the reaction substrates, streamlining the synthetic process and enhancing its practicality. Overall, this organoselenium-catalyzed C2,3-diarylation reaction presents an efficient and versatile strategy for the functionalization of indole derivatives.

Manipulated and Improved Photoinduced Deformation Property of Photoresponsive Liquid Crystal Elastomers by Copolymerization.

Photoresponsive liquid crystal elastomers (LCEs) have aroused much attention due to their unique structures, properties, and potential applications. However, many reported photoresponsive LCEs show small photoinduced deformation with a slow deformation speed, which limits their application to a certain extent. In this article, multiple hydrogen bond component and biphenyl component was introduced into photoresponsive LCEs bearing cyanostilbene by copolymerization, and prepared a series of LCEs CSm-BPn (CS and BP means cyanostilbene and biphenyl component, respectively; m, n means the content ratio of CS and BP). All uniaxially oriented CSm-BPn fibers show photoinduced deformation behavior under 365 nm UV light except for CS0-BP5. The introduction of hydrogen bond and the decrease of glass transition temperature realize large deformation and fast deformation speed. Besides, the properties of LCEs are successfully regulated by changing the content ratio of each component. What's more interesting is that the addition of appropriate amount of biphenyl can significantly improve and manipulate the deformation property of the CSm-BPn fibers. The maximum bending angle can reach 175° , and the whole photoinduced deformation process only takes 11 s. The photoresponsive LCEs with such large bending angle and fast deformation rate are rarely reported.

Ruthenium(II)-Catalyzed Remote C-H Sulfonylation of 2-Pyridones.

Herein, a ruthenium-mediated remote C-H mono- and disulfonylation of 2-pyridones with arylsulfonyl chlorides is developed. The catalytic system consisting of a [Ru(p-cymene)Cl2]2 catalyst and KOAc additive allows 2-pyridones to undergo C3,C5-disulfonylation in 1,4-dioxane, and C5-sulfonylation when the C3-position of 2-pyridones is blocked. The successful transformation of the products and late-stage modification of estrone further highlighted the potential utility and significance of this synthetic protocol. Preliminary mechanistic studies indicated that the remote regioselectivity might be dictated via chelation-assisted ruthenation.

Association between fatty acids and the risk of impaired glucose tolerance and type 2 diabetes mellitus in American adults: NHANES 2005-2016.

BACKGROUND: Fatty acids (FAs) play a major role in regulating insulin sensitivity. However, owing to dietary quantitative tools, it has been challenging to study the dietary FAs in previous studies. There is a lack of knowledge regarding the associations between dietary FAs and the risk of impaired glucose tolerance (IGT) and type 2 diabetes mellitus (T2DM). METHODS: Dietary FAs, adjustment of variables including age, sex, race, educational level, poverty to income ratio, body mass index, smoking, hypertension, physical activity, and diabetes data were extracted from the National Health and Nutrition Examination Survey 2005-2016. A multivariate logistic regression model was used to determine the associations between FA intake and the risk of IGT and T2DM. RESULTS: This serial cross-sectional study included 9082 samples. After adjusting all the variables, a negative correlation was observed between total saturated FA and the risk of IGT (OR = 0.991, 95% (CI): 0.985-0.998, P = 0.024). Total FA at quintile 4 was negatively correlated with T2DM (OR = 0.714, 95% CI: 0.532-0.959, P = 0.025) compared with quintile 1. Factor analysis identified four factors of which F4 was negatively associated with the risk of T2DM (OR = 0.824, 95% CI: 0.715-0.949, P = 0.029). Based on this factor, we identified an unsaturated FA signature (n = 4 FAs, including octadecenoic acid (18:1), octadecadienoic acid (18:2), octadecatrienoic acid (18:3), and eicosenoic acid (20:1)). CONCLUSIONS: Several unsaturated FAs with high proportions in natural oils may reduce the risk of T2DM.