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SIGNIFICANCE: Ergothioneine (ET) is an unusual sulfur-containing amino acid derived from histidine, acquired predominantly from food. Its depletion is associated with deleterious consequences in response to stress stimuli in cell culture models, prompting us to classify it as a vitamin in 2010, which was later supported by in vivo studies. ET is obtained from a variety of foods and is taken up by a selective transporter. ET possesses antioxidant and anti-inflammatory properties that confer cytoprotection. ET crosses the blood–brain barrier and has been reported to have beneficial effects in the brain. In this study, we discuss the cytoprotective and neuroprotective properties of ET, which may be harnessed for combating neurodegeneration and decline during aging. RECENT ADVANCES: The designation of ET as a stress vitamin is gaining momentum, opening a new field of investigation involving small molecules that are essential for optimal physiological functioning and maintenance of health span. CRITICAL ISSUES: Although ET was discovered more than a century ago, its physiological functions are still being elucidated, especially in the brain. As ET is present in most foods, toxicity associated with its deprivation has been difficult to assess. FUTURE DIRECTIONS: Using genetically engineered cells and mice, it may now be possible to elucidate roles of ET. This coupled with advances in genomics and metabolomics may lead to identification of ET function. As ET is a stable antioxidant with anti-inflammatory properties, whose levels decline during aging, supplementing ET in the diet or consuming an ET-rich diet may prove beneficial. Antioxid. Redox Signal. 36, 1306–1317.

The development of green and convenient methods for C–S bond formation has received significant attention because C–S bond widely occurs in many important pharmaceutical and biological compounds. Recently, visible-light photoredox catalysis has been established as an efficient and general tool for the construction of C–C and C-heteroatom bonds. In this review, we have focused on the research on recent advances in C–S bond formation via visible-light photoredox catalysis, and the growing opportunities they present to the construction of complex chemical scaffolds for applications encompassing bioactive molecules synthesis, synthetic methodology development, and sulfur-containing drugs. We hope that this review will provide chemists with a synthetic tool that will open the door to further development of organsulfur chemistry

In this investigation, a series of novel random bio-based thiophene–aromatic copolyesters, including thiophene and phenyl units, were successfully prepared from dimethyl 2,5-thiophenedicarboxylate, dimethyl 2,5-dimethoxyterephthalate, and the aliphatic diols ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol and 1,8-octanediol, via twostep melt polymerization as a facile and green semi-continuous process. Techniques used to monitor the polymerization process included Fourier transform infrared (FTIR) and proton nuclear magnetic resonance spectroscopy (1H NMR), gel permeation chromatography (GPC), differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical analysis. The copolymers had tunable Tg values ranging from 47–120°C, while their 5% decomposition temperature (Td, 5%) under N2 varied from 405–370 °C. GPC analysis showed that the polyesters had weight-average molecular weights (Mw) of 41 400–48 500 g/mol and polydispersity indices of 1.47–2.24. A study of structure-property relations showed that the properties of these copolymers can be tailored by varying their composition. All the copolyesters exhibited high tensile strength (45–80 MPa) and toughness values (elongation at break of 200–540%). After 28 weeks of incubation in humid soil, weight losses of up to 7.2% were observed. Considering their good mechanical properties, thermal stability and biodegradability, these renewable sulfur-containing copolyesters have great potential to replace petroleum-based commercial poly(ethylene terephthalate) in the food packaging industry, which is helpful to implement carbon neutrality and sustainable development in the polymer industry.

Sulfur-containing organic compounds display wide applications in the field of materials science, synthetic chemistry, and pharmaceutical industry. Thus, numerous synthetic strategies have been developed for the synthesis of sulfur-containing compounds in synthetic chemistry. In recent years, the utilization of sulfinic acids as versatile synthons has emerged as attractive and powerful approach to access various organosulfur compounds through sulfonylation, sulfinylation or sulfenylation reactions. In this review, we summarized the recent progress in the construction of various sulfur-containing compounds from sulfininc acids. Selected examples of substrates and the related reaction mechanisms are described here. This review intends to provide readers a comprehensive understanding on the synthesis of sulfur-containing molecules from sulfinic acids and provide help for future synthetic research.

Coke and sulfur poisoning was a major challenge for the decomposition of methyl mercaptan (CH3SH). Here, we focused on regulating the reaction pathway to solve the problem instead of adjusting the preparation methods of catalyst. In this study, Ce/MCM-41 catalyst exhibited good stability (approximately 100 h) in dealing with coke/sulfur poisoning, which were ascribed to the size induced change in the properties of active centers where the transformation of CeO2 nanoparticles into CeO2 cluster-scale particles altered the active centers from surface reactive oxygen to strong acid sites. Most of the sulfur elements of CH3SH were converted into H2S and CS2 by these strong acid sites, avoiding the excessive accumulation of sulfide/sulfur on the catalyst, as verified by XRD, XPS, and in situ FT-IR analysis. This work reveals the new reaction pathway and deactivation mechanism of Ce-based catalysts, which provides a promising strategy for the development of a high coke/sulfur-tolerance catalyst for eliminating sulfur-containing organic compounds.