Photoinduced decatungstate-catalyzed C(sp3)-H thioetherification by sulfinate salts.

Thiols and thioesters play crucial roles in pharmaceuticals, biology, and material science as essential organosulfur compounds. Leveraging readily available and cost-effective inert alkanes through direct thioetherification holds promise for yielding high-value-added products. Herein, we present a photoinduced strategy for sulfur-containing modification of inert alkanes utilizing decatungstate as hydrogen atom transfer reagent, offering a straightforward and practical approach for synthesizing thioethers and thioesters.

Photoelectrochemical oxidative C(sp3)-H borylation of unactivated hydrocarbons.

Organoboron compounds are of high significance in organic synthesis due to the unique versatility of boryl substituents to access further modifications. The high demand for the incorporation of boryl moieties into molecular structures has witnessed significant progress, particularly in the C(sp3)-H borylation of hydrocarbons. Taking advantage of special characteristics of photo/electrochemistry, we herein describe the development of an oxidative C(sp3)-H borylation reaction under metal- and oxidant-free conditions, enabled by photoelectrochemical strategy. The reaction exhibits broad substrate scope (>57 examples), and includes the use of simple alkanes, halides, silanes, ketones, esters and nitriles as viable substrates. Notably, unconventional regioselectivity of C(sp3)-H borylation is achieved, with the coupling site of C(sp3)-H borylation selectively located in the distal methyl group. Our method is operationally simple and easily scalable, and offers a feasible approach for the one-step synthesis of high-value organoboron building blocks from simple hydrocarbons, which would provide ample opportunities for drug discovery.

Iron-Catalyzed C(Sp3)-H Borylation, Thiolation, and Sulfinylation Enabled by Photoinduced Ligand-to-Metal Charge Transfer.

Catalytic C(sp3)-H functionalization has provided enormous opportunities to construct organic molecules, facilitating the derivatization of complex pharmaceutical compounds. Within this framework, direct hydrogen atom transfer (HAT) photocatalysis becomes an appealing approach to this goal. However, the viable substrates utilized in these protocols are limited, and the site selectivity shows preference to activated and thermodynamically favored C(sp3)-H bonds. Herein, we describe the development of undirected iron-catalyzed C(sp3)-H borylation, thiolation, and sulfinylation reactions enabled by the photoinduced ligand-to-metal charge transfer (LMCT) process. These reactions exhibit remarkably broad substrate scope (>150 examples in total), and most importantly, all of these three reactions show unconventional regioselectivity, with the occurrence of C(sp3)-H borylation, thiolation, and sulfinylation preferentially at the distal methyl position. The procedures are operationally simple and readily scalable and provide access to high-value products from simple hydrocarbons in one step. Mechanistic studies and control experiments indicate that the afforded site selectivity is not only relevant to the HAT species but also largely affected by the use of boron- and sulfone-based radical acceptors.

Bacillus coagulans 13002 and fructo-oligosaccharides improve the immunity of mice with immunosuppression induced by cyclophosphamide through modulating intestinal-derived and fecal microbiota.

This study aims to evaluate the effects of probiotic Bacillus coagulans 13,002 (BCS) and prebiotic fructo-oligosaccharides (FOS) on mice treated with the alkylating agent cyclophosphamide (CTX). We found that both BCS and FOS, especially BCS, significantly alleviated CTX-induced injury by modulating intestinal-derived and fecal microbiota. BCS and BCS + FOS increased serum immunoglobulin levels, which were reduced by CTX. In addition, BCS and BCS + FOS upregulated IFN-γ and IL-4, which protect mucosal barriers and the balance of Th1/Th2. BCS promoted the growth of some beneficial bacteria, such as Bacteroides, Coprococcus, Enterococcus, Oscillospira, and Ruminococcus in mouse gut. In addition, BCS + FOS inhibited the growth of several harmful bacteria, including Acinetobacter, Arthrobacter, Brachybacterium, Corynebacterium, Jeotgalicoccus, Sporosarcina, and Staphylococcus. Furthermore, BCS potentially improved the growth of Anaerotruncus bacteria, which can promote the production of butyrate acids. In summary, according our results suggest that BCS and FOS improved the immunity of mice with immunosuppression induced by CTX through modulating intestinal-derived and fecal microbiota.

Iminyl-Radical-Promoted C-C Bond Cleavage/Heck-Like Coupling via Dual Cobaloxime and Photoredox Catalysis.

We report herein an unprecedented protocol for radical-olefin coupling of α-imino-oxy acids and alkenes for the synthesis of alkene-containing nitriles via synergistic photoredox and cobaloxime catalysis. With visible-light irradiation, the transformation provides a variety of corresponding alkene-containing nitriles under mild reaction conditions. The C-C bond cleavage/Heck-like coupling reaction could generate E-selective coupling products with excellent chemo- and stereo-selectivity. This iminyl-radical-mediated reaction is external-oxidant-free, exhibits wide functional-group compatibility, and occurs with the extrusion of acetone, H2, and CO2.

Visible-Light-Promoted Intramolecular α-Allylation of Aldehydes in the Absence of Sacrificial Hydrogen Acceptors.

We report herein an unprecedented protocol for radical cyclization of aldehydes with pendant alkenes via synergistic photoredox, cobaloxime, and amine catalysis. The transformation was achieved in the absence of external oxidants, providing a variety of 5-, 6-, and 7-membered ring products with alkene transposition in satisfactory yields. The reaction exhibits wide functional group compatibility and occurs under mild conditions with extrusion of H2.

Radical Aza-Cyclization of α-Imino-oxy Acids for Synthesis of Alkene-Containing N-Heterocycles via Dual Cobaloxime and Photoredox Catalysis.

Nitrogen-containing heterocycles are prevalent in both naturally and synthetically bioactive molecules. We report herein an unprecedented protocol for radical aza-cyclization of α-imino-oxy acids with pendant alkenes via synergistic photoredox and cobaloxime catalysis. With or without alkenes as the intermolecular cross-coupling partners, the transformation provides a variety of corresponding alkene-containing dihydropyrrole products in satisfactory yields. In the presence of external alkenes, the tandem reaction generates E-selective coupling products with excellent chemo- and stereoselectivity.

Ni-Catalyzed deaminative hydroalkylation of internal alkynes.

A regioselective cis-hydroalkylation of internal alkynes with readily prepared Katritzky pyridinium salts for the synthesis of tri-substituted alkenes is described. This reaction is the first example of a metal-catalyzed hydroalkylation of an alkyne via C-N bond activation of an amine. The reaction demonstrates broad scope and functional group tolerance, allowing access to desired products with high diversity. Preliminary mechanistic studies indicate that a combination of an SET-initiated radical process and Ni-catalyzed alkylation could engage in the reaction, which makes it possible to bypass the traditional open-shell addition pathway.

[Detecting effect comparison between MPAIA, DDIA and IHA for screening advanced schistosomiasis].

OBJECTIVE: To evaluate the effects of the magnetic particle antibody immunoassay (MPAIA), dipstick dye immunoassay (DDIA) and indirect hemagglutination assay (IHA), on detecting advanced schistosomiasis. METHODS: The sera of 224 cases of advanced schistosomiasis were detected by MPAIA, DDIA, and IHA, and the positive rates were compared. RESULTS: The positive rates of MPAIA, DDIA and IHA, were 67.14%, 14.29% and 16.52%, respectively,the positive coincidence rate of MPAIA is higher than the one of IHA and DDIA. CONCLUSION: The value of MPAIA is higher than that of DDIA or IHA in screening advanced schistosomiasis.