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An electrochemical C-H acylation of electron-deficient N-heteroarenes with α-keto acids is reported. This first electrochemical Minisci acylation reaction proceeded using NHI as a redox catalyst. A broad N-heteroarene scope and high functional group tolerance are observed. Selective monoacylation of N-heteroarenes is achieved via control of acyl radical at a low concentration. The results of cyclic voltammetry and control experiments disclose that the electrogenerated I is likely the active species to initiate the oxidative decarboxylation of carboxylate anion via an acyl hypoiodite intermediate. The electrochemical Minisci acylation provides a straightforward approach for the late-stage functionalization of pharmacophores.

A green electrochemical method of preparing diacid-disulfides has been developed, in which an SÀ S bond is formed by electrochemically oxidative coupling of SÀ H/SÀ H employing redox active NaI as mediator. The reactions are carried out in a simple undivided cell under constant current condition at room temperature and complete in 1.3 h to afford a series of diaciddisulfides with up to 97 % yields.

The new fluorescent probe 4-hydroxy-3-((2E,4E)-5-phenylpenta-2,4-dienoyl)-2H-chromen-2-one (probe 1) was designed and synthesized for selective detection of sulfite. The fluorescence intensity of the probe was decreased only in the presence of HSO; all other anions assessed resulted in an increased fluorescence response. Hence, probe 1 acts as a highly selective sensor for HSO. This sulfite sensitivity can also be readily monitored visually, as once treated with sulfite the solution shows a marked color change from yellow to colorless. Moreover, probe 1 can be conveniently used as a signal tool to determine the HSO levels in various sugar samples.

The problem of food spoilage due to Aspergillus flavus (A. flavus) needs to be resolved. In this study, we found that the minimum inhibitory concentration of cinnamaldehyde (CA) that inhibited A. flavus was 0.065 mg/ml and that corn can be prevented from spoiling at a concentration of 0.13 mg/cm 3. In addition to inhibiting spore germination, mycelial growth, and biomass production, CA can also reduce ergosterol synthesis and can cause cytomembrane damage. Our intention was to elucidate the antifungal mechanism of CA. Flow cytometry, fluorescence microscopy, and western blot were used to reveal that different concentrations of CA can cause a series of apoptotic events in A. flavus, including elevated Ca 2+ and reactive oxygen species, decrease in mitochondrial membrane potential (ψ m), the release of cytochrome c, the activation of metacaspase, phosphatidylserine (PS) externalization, and DNA damage. Moreover, CA significantly increased the expression levels of apoptosis-related genes (Mst3, Stm1, AMID, Yca1, DAP3, and HtrA2). In summary, our results indicate that CA is a promising antifungal agent for use in food preservation.

The preparation of nitriles from primary amides or aldoximes was achieved by using oxalyl chloride with a catalytic amount of dimethyl sulfoxide in the presence of Et3N. The reactions were complete within 1 h after addition at room temperature. A diverse range of cyano compounds were obtained in good to excellent yields, including aromatic, heteroaromatic, cyclic, and acyclic aliphatic species.

No abstract

An efficient protocol for the synthesis of 3-aminoquinoxalinones via the electrochemical dehydrogenative C-3 amination of quinoxalin-2(1H)-ones was developed. With aliphatic amines and azoles as the nitrogen sources, a series of 3-aminoquinoxalinones was obtained in up to 99% yield. This direct electrolytic method avoids the use of transition metals and external oxidants, and represents an appealing alternative for the synthesis of 3-aminoquinoxalinones.