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We introduced an electrochemical oxidative radical cascade cyclization of olefinic amides and diselenides without a transition-metal catalyst and external oxidant. This selenocyclization reaction provided a facile method to construct C–Se and C–O bonds in one step.

In this context, we used an electrochemical reduction method to obtain thiyl radicals from sulfinic acids. In a simple undivided cell, various acyl chlorides and sulfinic acids were compatible, generating 40 examples of the desired thioesters.

A highly stereoselective synthesis of thiocyanated enaminones was achieved by an electrochemical process, which involved C–H bond thiocyanation and vinyl C–N bond transamination. Various aryl enaminones were compatible, generating the desired thiocyanated enaminones in up to 87% yields. This transformation proceeded smoothly without an external oxidant, a supporting electrolyte and a transition-metal catalyst. Gram-scale synthesis showed the potential of this protocol for practical application.

Heterocycles containing N and O are important structures in pharmaceuticals, agrochemicals and functional molecules. The synthesis of these compounds usually requires complex substrates and harsh reaction conditions. Herein, we introduce a mild and efficient electrochemical oxidative strategy to construct benzoxazines, oxazolines and iminoisobenzofurans without the requirement of a transition-metal catalyst and an external oxidant. In a simple undivided cell, various olefinic amides and thiophenols/diselenides react to generate 69 examples of thiolation and selenylation heterocycles in up to 83% yields. Furthermore, this radical cascade reaction provided a facile method for constructing C–S/C–Se and C–O bonds in one step.

A direct electrochemical oxidation of alkynes for the synthesis of benzoin bis-ethers has been developed. Various alkynes and alcohols are compatible, generating the desired products in up to 85% yield. This transformation can be performed under mild reaction conditions in the absence of an external oxidant and transition metal catalyst. Preliminary mechanism studies suggest that the product carbonyl oxygen originated from water.

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. Although host surface annexin a2 (ANXA2) has been identified to participate in efficient bacterial invasion of epithelial cells, direct evidence is lacking in the field of bacterial infections of ECs. In the present study, we employ a novel, anatomically based, in vivo quantitative bacterial-adhesion-to-vascular-EC system, combined with atomic force microscopy (AFM), to examine the role of endothelial luminal surface ANXA2 during rickettsial adherence to ECs. We also examined whether ANXA2 antibody affected binding of Staphylococcus aureus to ECs. We found that deletion of ANXA2 impeded rickettsial attachment to the ECs in vitro and blocked rickettsial adherence to the blood vessel luminal surface in vivo. The AFM studies established that EC surface ANXA2 acts as an adherence receptor for rickettsiae, and that rickettsial adhesin OmpB is the associated bacterial ligand. Furthermore, pretreatment of ECs with anti-ANXA2 antibody reduced EC surface-associated S. aureus. We conclude that the endothelial surface ANXA2 plays an important role in initiating pathogen–host interactions, ultimately leading to bacterial anchoring on the vascular luminal surface.

Photocatalytic decarboxylative cross-coupling which achieves the derivatization of widespread organic acids has become a hot topic in organic synthesis. As special acids, α-oxocarboxylicacids show the great potential in running decarboxylation to construct ketone derivatives. In this article, we have developed a photocatalytic decarboxylative cross-coupling of α-oxocarboxylic acids and olefins to the synthesis of diverse aryl ketones. Various alkenes and α-oxocarboxylicacids were compatible, generating the desired products in up to 90% yield. Preliminary mechanism studies suggest that a free radical pathway is involved in this process.

An electrochemical oxidative C(sp2)-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. Remarkably, thiophenols selectively coupled with enamines when substrates had other alkenyl groups. In addition, the desired products could be further transformed into a series of α-sulfur isoxazoles, which are a kind of useful heterocycles in materials and bioactive molecules.

The first copper-catalyzed cross-couplings of thiophenols with benzyltrimethylammonium triflates was developed. Various kinds of aryl thiophenols, heteroaryl thiophenols and alkylthiols demonstrated to be efficient substrates, generating the desired alkyl thioethers in moderate to good yields. Meanwhile, different benzyltrimethylammonium triflates could be well tolerated.

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. Therefore, on the basis of the persistent radical effect, selective radical–radical cross-coupling between the thiyl radical and the isobutyronitrile radical was achieved successfully in this work.

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.

In this paper based on the traditional stochastic inventory control problem, namely, the Newsboy problem, considered the factor of inventory item which has an impact on the decision-making model, a new model is built up. While assuming the form of demand to meet the adding form, and considering the impact of the price on the demand rate and the impact of the demand rate on inventory item, we discuss a new subscription model, and give corresponding calculation methods to determine the optimal order quantity and optimal sales price. Model in this paper is an extension of existing models, while the known model is a special case of this model. At last an simple example is given.