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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.

Originating from “rocking‐chair concept”, lithium‐ion batteries (LIBs) have become one of the most important electrochemical energy storage technologies, which have largely impacted our daily life. The utilization of electrolyte additives in small quantities (≤5% by wt or vol) has been long viewed as an economical and efficient approach to regulate the properties of electrolyte and electrode–electrolyte interphases and consequently improve the cycling performance of LIBs. Among all the kinds of electrolyte additives, sulfur‐containing compounds have gained significant attention due to their unique features in building stable electrode–electrolyte interphases and protect battery cells from overcharging. In this work, advances and progresses of sulfur‐containing additives used in LIBs are overviewed, with special attention paid to the working mechanisms of these electrolyte additives. Particularly, four representative sulfur‐containing compounds (i.e., 1,3‐propane sultone, prop‐1‐ene‐1,3‐sultone, 1,3,2‐dioxathiolane‐2,2‐dioxide, and ethylene sulfite) are comparatively discussed concerning their impact on electrode–electrolyte interphases and cell performances. Future work on the development of sulfur‐containing compounds as functional electrolyte additives is also provided. The present review is anticipated to be not only a base document to access the status quo in this research domain but also a guideline to select specialized additives and electrolytes for practical applications.

This paper analyses the possibility for H2SO4 production using sulfur/sulfur-containing feedstocks from Dung Quat Refinery in terms of market, technology and economic efficiency. Domestic production of H2SO4 currently does not meet the domestic demand, the shortfall must therefore be compensated by imports. It is forecast that the domestic market will lack about 464 thousand tons of H2SO4 by 2025. The H2SO4 production project with a capacity of 200 thousand tons per year is proposed to go into operation in 2025. In the case of indirect production of H2SO4 from H2S rich gas through the intermediate sulfur product, the project has an estimated total investment cost of USD 143.2 million, its IRR will be around 3.2%, its NPV@13.2% will be USD 55.1 million and the total payback period will be 14 years and 4 months. In case of using H2S rich gas directly as feedstock, the project has an estimated total investment cost of USD 102.4 million, its IRR will be around 16.3%, its NPV@13.2% will be USD 15.7 million and the total payback period will be 5 years and 5 months.

Cesium lead halide perovskite nanocrystals (NCs) are the most promising materials for photovoltaic and optoelectronic applications in recent years. However, lack of long-term stability and conseque...

The present paper considers the study of creep and deformation properties of sulfur-containing arbolit exposed to various compression stresses. Investigating the creep of lightweight arbolit concretes greatly affecting the performance of bearing and envelope structures draws a special attention during the last years. This issue is of particular relevance in the regions with hot and sharp continental climate. Arbolit concrete is one of the lightest building materials with low thermal conductivity and good soundproof properties. The modern postulates of theory and practice of creation, development of high-strength arbolit concretes on the base of composite sulfur-containing binders have become the methodological framework of the present research. While carrying out scientific research, the following standard measuring and analysis methods of physical and mechanical properties have been used for sulfur-containing arbolit composites. Experimental tests have been implemented on the 28-days samples made of sulfur-containing arbolit, with the cotton plant footstalks as an organic component. The researched samples were vapor sealed with the purpose to eliminate overlapping the processes of contraction and creep. The experimental results have shown that the analysis of prisms deformation in time demonstrates certain derivation from the pattern. Deformation of prisms made of sulfur-containing arbolit loaded at the low stress level were growing at a slower rate that the same deformations at a higher stress level. No derivation has been observed for the prisms of sulfur-containing haydite concrete. For both types of concrete, creep deformation has reached the values exceeding completely recoverable deformation by a factor of 2 or all the samples, the rapid growth of creep deformation has been observed after loading, followed by the gradual slowdown of deformation growth. For sulfur-containing lightweight concretes, as the test shown, the rate of creep deformation growth depends on the hardening curve in time reflecting the process of concrete hardening. This, if compared with sulfur-containing lightweight concretes, creep of sulfur-containing arbolit concrete is significantly lower that eventually leads to the loss of creep deformation at the same stress level. The obtained results can be used when manufacturing an efficient wall material for residential construction, including seismic areas.

The article presents information on the synthesis of epoxy oligomers based on 2,2-di-(4-hydroxyphenyl) sulfone (DODPS) and hexachloroethane (HCE). We showed the results of a study of the adhesive properties and fire resistance of epoxy polymers. The synthesized sulfur-containing epoxy oligomers have a reasonably low viscosity and high fire resistance. Casting compounds obtained on their basis have improved performance characteristics.

Analysis of literature sources, as well as practical data indicate that the existing scientific, technical and technological developments to ensure reliable corrosion-mechanical resistance and durability of oil and gas pipelines and other shell metal structures of critical use and subordinate to the State Service for Mining Supervision and Industrial Safety of Ukraine largely find contradictions and uncertainty; there are no quantitatively substantiated recommendations for practical application in order to ensure corrosion and mechanical resistance of pipelines operating in technologically aggressive environments under alternating temperature and barometric conditions and loads; there is a need for a systematic study of the causes, conditions and mechanisms of corrosion and mechanical damage of long-term equipment, which will significantly increase the operational reliability of industrial equipment. Experimental studies have established the causes and substantiated the mechanisms of metal softening with increasing service life (from 0 to 25 years) that leads to its degradation, especially during long-term operation in corrosive environments. A method for forecasting the residual working (accident-free) life of pipeline metal structures has been developed, which makes it possible to purposefully regulate their operational condition. This allows the timely use of technical, design and technological measures to improve the performance of such structures. Numerous and diverse results of experimental tests of metal samples for various purposes have been obtained, which provide an opportunity to create a base for comparative analysis of steels in many parameters of crack resistance, which will become a reliable basis for scientific and practical substantiation of the equivalent replacement of some steel grades with other grades, taking into account technological loads, corrosive environments and others.

In the paper, bulk property and chemical composition of Kazakhstan vacuum residuum were characterized. Sulfides and thiophenes were selectively isolated from the residuum and characterized by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Molecular weights of the sulfur compounds were varied from 150 to 800 Da and S1 , S2 , O1S1 , O2S1 , N1S1 class species were assigned in the heavy oil derived methylsulfonium. Vanadyl porphyrins characterized by positive-ion electrospray ionization and FT-ICR MS, which showed that etioporphyrins (ETIO) (CnH2n-28N4V1O1 , corresponding to DBE = 17) and deoxophylloerythroetioporphyrins (DPEP) (CnH2n-30N4V1O1, corresponding to DBE = 18). It should be noted that the vanadyl porphyrins were most abundant.

Summary The enzymatic conversion of l‐methionine (l‐Met) into volatile organic sulfur‐containing compounds (VOSCs) plays an important role in developing the characteristic aroma of foods. However, the mechanism for the direct conversion of l‐Met into VOSCs is still unclear in yeast cells used to make food products. Here, we show that the transcription profile of YALI0C22088g from Yarrowia lipolytica correlates positively with l‐Met addition. YALI0C22088g catalyses the γ‐elimination of l‐Met, directly converting l‐Met into VOSCs. YALI0C22088g also exhibits strong C‐S lysis activities towards l‐cystathionine and the other sulfur‐containing compounds and forms a distinct cystathionine‐γ‐lyase subgroup. We identified eight key amino acid residues in YALI0C22088g, and we inferred that the size of the tunnel and the charges carried by the entrance amino acid residue are the determinants for the enzymatic conversion of l‐Met into VOSCs. These findings reveal the formation mechanism of VOSCs produced directly from l‐Met via the demethiolation pathway in Yarrowia lipolytica, which provides a rationale for engineering the enzymatic conversion of l‐Met into VOSCs and thus stimulates the enzymatic production of aroma compounds., YALI0C22088g from Yarrowia lipolytica catalyses the γ‐elimination of l‐methionine, directly converting l‐methionine into VOSCs. YALI0C22088g also exhibits strong C‐S lysis activities toward the other sulfur‐containing compounds and forms a distinct cystathionine‐γ‐lyase subgroup. The size of the tunnel and the charges carried by the entrance amino acid residues are inferred to be the determinants for the enzymatic conversion of l‐Met into VOSCs.

In this research, firstly, some derivatives of sulfur containing [1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one have been synthesized and then they were used for the synthesis of novel derivatives of 6′-amino-2,9′-dioxo-2′-phenyl-9′H-spiro[indoline-3,8′-pyrano[2,3-d][1,3,4]thiadiazolo[3,2-a]pyrimidine]-7′-carbonitriles via a one-pot three-component condensation reaction of 7-hydroxy-2-phenyl-5H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one derivatives, malononitrile and isatin compounds in the presence of DABCO as a organocatalyst and under solvent-free conditions. In this report, a new family of spiro-pyrano-thiadiazolo-pyrimidine derivatives have been synthesized in short reaction times (10–60 min) and good to excellent yields (80–96%). The structures of all synthesized products have been confirmed by IR, 1H NMR, 13C NMR and mass spectrometry, and the structure of one selected product was characterized by single-crystal X-ray diffraction studies as well.

Natural products derived from marine microorganisms have received great attention as a potential resource of new compound entities for drug discovery. The unique marine environment brings us a large group of sulfur-containing natural products with abundant biological functionality including antitumor, antibiotic, anti-inflammatory and antiviral activities. We reviewed all the 484 sulfur-containing natural products (non-sulfated) isolated from marine microorganisms, of which 59.9% are thioethers, 29.8% are thiazole/thiazoline-containing compounds and 10.3% are sulfoxides, sulfones, thioesters and many others. A selection of 133 compounds was further discussed on their structure–activity relationships, mechanisms of action, biosynthesis, and druggability. This is the first systematic review on sulfur-containing natural products from marine microorganisms conducted from January 1987, when the first one was reported, to December 2020.

Background. Change of the content of sulfur-containing amino acids and their metabolites is one of the pathochemical mechanisms of alcohol intoxication. Purpose of the study. To study the effect of chronic and intermittent alcohol intoxication on the content of sulfurcontaining amino acids and related compounds in the rat blood plasma. Material and methods. Thirty white outbred rats weighing 180-220 g. The content of free amino acids and biogenic amines was determined by HPLC. Results. A 14-day chronic alcohol intoxication was accompanied by a significant decrease in the level of methionine and an increase in the level of homocysteine in the blood plasma. The concentration of glutathione increased by 5%. In the intermittent alcohol intoxication IAI-4 group, the homocysteine content also increased, as did the level of homoserine and cystathionine in the IAI-1 group. Conclusions. Сhronic and intermittent alcohol intoxications cause similar violations of the level of sulfur-containing amino acids and their metabolites in the rat blood plasma.

Detailed molecular analysis of complex mixtures such as crude oil and its fractions has been successfully covered by a number of groups during the past two decades. On the other side, the most glaring need is some type of method that allows quantitative analysis of a single class, compound species, or even individual compounds. Here, the problem is being complicated by the complexity of the sample and the need for individual response factors necessary for the analysis of single compounds in almost all analytical methods. This can be circumvented by using a method with uniform response like inductively coupled plasma-mass spectrometry. Sulfur is one of the most important heteroelements present in crude oil and its products due to stringent regulations. Quantification of sulfur by means of mass spectrometry has always been a challenging task. Here, we present the combination of a sulfur-selective chromatographic separation of crude oil and its fractions on a Pd-coated stationary phase with two-dimensional detection. Qualitative analysis by ultrahigh-resolution Orbitrap mass spectrometry allows a detailed understanding of individual compositions after chromatographic separation, while the quantitative data from inductively coupled plasma tandem mass spectrometry details the quantities of each part of the chromatogram. The combination of the results from both methods allows assigning three different types of sulfur species and their quantitative determination in extremely complex heavy crude oil fractions.

The application of Li-S batteries is hampered by some unresolved issues, including the severe polysulfides shuttle effects and sluggish reaction kinetics. Hence, we designed and prepared tin oxide ...

Oxidative desulfurization is a promising method to produce clean fuels with an ultralow sulfur content at mild conditions. Herein, for the first time, we present multifunctional ionic liquid cataly...

This research discusses the use of coal-processing wastes of the Shubarkol Deposit (Karaganda region, Kazakhstan) to produce valuable materials such as carbon fibers. Annually «Shubarkol Komir» JSC alone produces up to 35,000 tons of coal tar as byproduct. In this experiment, mesophase pitch was obtained by coal tar heat treatment at 200 o C. By cracking mesophase pitch into the pieces with the addition of poly (methyl methacrylate) as fiber-forming material and 1,2-dichloroethane as solvent, the spinnable solution was prepared. The elemental analysis of the mesophase pitch showed that the heat treatment up to 200 o C does not contribute to the full elimination of sulfur containing components that influence the forming of mesophase. From the Raman spectra of the pitch, the D peak appearance at ~ 1370 cm-1 and G peak at ~ 1600 cm-1 responsible for carbon products. Carbon fibers with an average diameter of 2.5-3.3 μm were obtained by electrospinning technique in laboratory settings. References [1] The official web site of the International Energy Agency (IEA) https://www.iea.org/ [2] Kim B.J., Kil H., Watanabe N., Seo M.H., Kim B.H., Yang K.S., Kato O., Miyawaki J., Mochida I., Yoon S.H. // Curr Org Chem. 2013, 17, 1463. http://doi.org/10.2174/1385272811317130013 [3] Zhu J., Park S.W., Joh H.I., Kim H.C., Lee S. // Carbon Lett. 2013, 14, 94. http://doi.org/10.5714/CL.2013.14.2.094 [4] https://www.erg.kz/ru/news/693 [5] Derbyshire F., Andrews R., Jacques, D. Jagtoyen M., Kimber G., Rantell T.. // Fuel. 2001, 80, 345. http:/doi.org/10.1016/S0016-2361 (00)00099-5 [6] https://www.bp.com/content/dam/bp/business-sites/en/global/corporate/pdfs/energy-economics/statistical-review/bp-stats-review-2020-full-report.pdf [7] Forintos N., Czigany T. Composites Part B: Engineering, 2019, 162, 331. https://doi.org/ 10.1016/j.compositesb.2018.10.098 [8] Aldosari S.M., Khan M., Rahatekar S. // Journal of Materials Research and Technology. 2020, 9(4), 7786. http://doi.org/10.1016/j.jmrt.2020.05.037 [9] Doshlov O.I., Kondrat’ev V.V., Ugap’ev A.A. et al. // Coke Chem. 58, 32-38 (2015). https://doi.org/10.3103/S1068364X15010020 [10] Frank E., Steudle L.M., Ingildeev D., J. M. Sporl, M. R.:Buchmeiser, AngewChemInt Ed., 2014, 53, 5262. http://doi.org/10.1002/anie.201306129 [11] Yang K.S., Kim B.H., Yoon S.H. // Carbon Lett. 2014, 15, 162. http://doi.org/10.5714/CL.2014.15.3.162 [12] Mochida I., Toshima H., Korai Y., Matsumoto T. // J Mater Sci. 1988, 23, 670. https://doi.org/10.1007/BF01174704 [13] Zhiyuan C., He J., Fengwen Z., Yuexing L., Yong L., Huilin Y. // J. Serb. Chem. Soc. 2014, 79, 587. http://doi.org/10.2298/jsc130702150z [14] Yoo M.J., Ko H.J., Lim Y.S., Kim M.S. // Carbon Lett. 2014, 15, 247. http://dx.doi.org/10.5714/CL.2014.15.4.247 [15] Yermagambet B., Kazankapova M., Nauryzbaeva A., Mansurov Z., Smagulova G., Kai-dar B. // News of the NAS of RK. Ser. of Geo. Tech. Sc. 2019, 4, 436. https://doi.org/10.32014/2019.2518-170X.101 [16] Park S. Carbon Fibers, Springer Netherlands, Incheon, Republic of Korea (South Korea). 2015, 337. http://dx.doi.org/10.1007/978-94-017-9478-7 [17] Filippov M.M. Ramanovskaya spektroskopiya kak metod izucheniya gluboko ugleficirovannogo organicheskogo veshchestva // Russia, Petrozavodsk, 2014, 1, 115. http://igkrc.ru/assets/publication/trudy-2014-1-p115-134.pdf [18] Severyuhina A.N., Svenskaya Yu. I, Gorin D.A. // Izvestiya Saratovskogo universiteta. Novaya seriya. Seriya Fizika. 2013, 13(2), 67.

The economic evaluation of the exploration sulfur well depends mainly on the elemental sulfur content and its association other factors, so a sample of sulfur rocks extracted by a special excavator for one of the exploratory wells was studied and in the form of a bore hole rock. The elemental sulfur ratio reached 12.8% an important ratio in estimating the explored sulfur reserves and through XRD, the predominant crystalline composition is calcite mineral with hexagonal crystalline form and with a lesser percentage in orthorhombic crystal sulfur this supports one of the theories that explained the formation of sulfur. Also, the mine Mishraq sulfur extracted by the underground melting method (known as the Frasch process) was studied chemically, and the elemental sulfur ratio reached 98.58% and the bituminous material 1.157%. Also, the SEM scanning electron microscope showed the presence of nanotubes of size (20-44 nm) belonging to the carb-sulfur compounds in the SEM, which are observed for the first time in this form.

Цель исследования – изучить показатели концентраций серосодержащих аминокислот и их метаболитов в сыворотке крови у женщин с хирургической и естественной менопаузой и установить корреляционные взаимосвязи со степенью тяжести климактерического синдрома, уровнем гонадотропных и половых стероидных гормонов. Материал и методы. Нами обследованы 192 женщины, из них 93 с хирургической менопаузой (I группа), 68 с естественной менопаузой (II группа), 31 в позднем репродуктивном и пременопаузальном возрастах (контрольная группа). Пациенткам проводилось исследование содержания гомоцистеина (Hcy), цистеина (Cys), глутатиона (GSH) и цистеинилглицина (CysGly) в сыворотке крови методом высокоэффективной жидкостной хроматогафии (ВЭЖХ). Результаты. Установлено, что у женщин с хирургической менопаузой медианное значение показателей гомоцистеина, цистеина, цистеинилглицина в 1,5 раза, на 17,0% и 23,2% соответственно выше, чем у женщин с естественной менопаузой, и в 2,2, 2,0 и 1,8 раза соответственно выше, чем у пациенток контрольной группы (p

Sulfur is widely existent in natural products and synthetic organic compounds as organosulfur, which are often associated with a multitude of biological activities. OBenzothiazole, in which benzene ring is fused to the 4,5-positions of the thiazolerganosulfur compounds continue to garner increasing amounts of attention in the field of medicinal chemistry, especially in the development of therapeutic agents for Alzheimer's disease (AD). AD is a fatal neurodegenerative disease and the primary cause of age-related dementia posing severe societal and economic burdens. Unfortunately, there is no cure for AD. A lot of research has been conducted on sulfur-containing compounds in the context of AD due to their innate antioxidant potential and some are currently being evaluated in clinical trials. In this review, we have described emerging trends in the field, particularly the concept of multi-targeting and formulation of disease-modifying strategies. SAR, pharmacological targets, in vitro/vivo ADMET, efficacy in AD animal models, and applications in clinical trials of such sulfur compounds have also been discussed. This article provides a comprehensive review of organosulfur-based AD therapeutic agents and provides insights into their future development.

In this study, dibutyl sulfide (DS), phenyl sulfide (PS) and 2-methyl thiophene (2-MT) were selected as model compounds to investigate the effect of Fe3+ on sulfur release by pyrolysis connected with gas chromatography (Py-GC) and pyrolysis coupled with mass spectrometer (Py-MS) under Ar and 3% O2–Ar atmospheres. It is found that main forms of sulfur-containing gases are different during their pyrolysis under different atmospheres. Sulfur gases are mainly SO2 under 3% O2–Ar atmosphere. Under Ar atmosphere, PS is more difficult to decompose than 2-MT, while easier under 3% O2–Ar atmosphere. 0.5% Fe3+ only significantly promotes the sulfur release amount of PS under Ar atmosphere. However, 2% Fe3+ is more effective for DS and 2-MT to decompose under Ar atmosphere and it promotes all these sulfur gases release at lower temperatures under Ar atmosphere. And 2% Fe3+ is more beneficial for all these three compounds to decompose under 3%O2–Ar atmosphere than 0.5% Fe3+, especially for PS. Therefore, 2% Fe3+ can more efficiently promote sulfurs release of these sulfur compounds.

Sulfur-containing polymers are polymers containing at least one sulfur atom in the repeat units of their main chains. The incorporation of sulfur atoms into the polymer main chains endows polymers with enhanced properties in many areas, including improved mechanical properties, optical properties, thermal properties, and adhesive abilities toward metal ions. Such enhanced properties make sulfur-containing polymers promising polymeric materials. In terms of environmental issues caused by waste plastic, the utilization of sulfur-containing polymers is also appealing from the aspect of degradability. Hence, degradable sulfur-containing polymers, including poly(thiocarbonate)s, poly(thioester)s, and poly(sulfite)s, are drawing more and more attention. However, the synthesis of these polymers involves problems like mixed structures and weak stereochemistry control of the resultant polymers due to the intrinsic properties of sulfur atoms, such as strong nucleophilicity and coordinative abilities. Thus, tackling the problems caused by sulfur chemistry is the main challenge relating to the precise synthesis of sulfur-containing polymers. Herein, this review describes recent progress made regarding the precise synthesis of sulfur-containing polymers from the perspectives of structure control, stereochemistry control, and topological structure modification.

Recycling platinum group metals from secondary resources has always been a difficult task in research. In this work, the extraction and separation of Pd(II)/Pt(IV) by the application of 2-mercaptobenzimidazole from hydrochloric acid medium was investigated. At first, the effects of the experimental conditions were studied to optimize the parameters of extraction and separation, such as time, acidity, salinity and extractant concentration. Then, the extraction mechanisms of Pd(II)/Pt(IV) were confirmed by UV-vis, FT-IR and electrostatic potential (ESP) map analysis. Moreover, through the screening of various stripping agents, a feasible strategy to separate Pd(II)/Pt (IV) was proposed. Subsequently, 92.1% Pd(II) and 98.7% Pt(IV) were successfully obtained by two-stage extraction and Pd(II)/Pt(IV) were separated from the loaded organic phase using thiourea as the stripping agent. Finally, 2-mercaptobenzimidazole also showed excellent selectivity for recovering individual Pd(II)/Pt(IV) from multi-metal solutions.

Sulfonium salts and sulfur ylides are important S(IV) motifs, and have displayed many unique reactivities to provide simple, effective, and often stereoselective synthesis toward sulfur containing compounds. Impressive developments have been witnessed within this field during the past several years. In light of the increasing demand of organosulfur compounds across the range of chemical sciences, our aim of this review is to provide a concise overview of recent advances of sulfonium salt and sulfur ylide chemistry. Selected examples are organized in three parts on the basis of their role in organic reactions (reactants, intermediates and catalysts).

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To further study the mechanism of coal self-heating, the reaction sequences and thermodynamic properties between sulfur-containing groups and oxygen during coal self-heating were analyzed. The benzyl mercaptan and diphenyl sulfide were selected as typical sulfur-containing structures existing in coal. Their structural parameters, frontier orbital characteristics, and thermodynamic parameters were analyzed through quantum chemistry calculation and their detailed reaction sequences with oxygen were proposed. The results indicate that the thiol structure in coal can easily react with oxygen at low temperatures and release large amounts of heat (146.70 kJ/mol) during coal self-heating, providing active free radicals and energy for subsequent chain reactions of coal spontaneous combustion. The oxidation reaction between the thioether structure and oxygen cannot occur at room temperature. With the accumulation of heat, thioether gradually becomes active and reacts with oxygen to form sulfoxide and release an enormous amount of heat (248.09 kJ/mol), which can be further oxidized to sulfone with an increase in temperature. The reaction models of thiol and thioether groups during coal self-heating were proposed, which involves eight main reaction sequences (R1∼R8). It indicates that the reactions of thiol and thioether groups play crucial roles during the evolution of coal self-heating, with a slow oxidation stage at low temperatures and an accelerated oxidation stage at high temperatures.

We studied two types of palladium-containing catalysts in the hydrogenation reaction of a model feedstock in order to reveal contacts resistance to sulfur, and it was shown that the decrease in the activity of catalysts upon the action of thiophene is associated with the number of electron-seeking centers on their surface. An assumption was made about the hydrogenation proceeding according to two schemes, depending on the type of catalyst

A chiral phosphoric acid-catalyzed enantioselective 1,6-conjugate addition of thiolacetic acid to alkynyl indole imine methide in situ formed from α-(3-indolyl) propargylic alcohol has been established, which enables the formation of axially chiral sulfur-containing tetrasubstituted allenes in generally high efficiency with stereoselectivity.

An efficient ruthenium-catalyzed method has been developed for the direct N-alkylation of sulfur-containing amines with alcohols, for the first time, by a step-economical and environmentally friendly hydrogen borrowing strategy. The present methodology features base-free conditions and broad substrate scope, with water being the only by-product. Moreover, this protocol has been applied to the synthesis of the pharmaceutical drug Quetiapine.

Nowadays the search of new high-efficiency and safe drugs for the pharmacotherapy of diseases accompanied by pain syndrome is an active area of modern pharmacological research. 170 new derivatives of di- and tetrahydropyridines synthesized on the basis of the Chemex Research Laboratory, Vladimir Dahl Lugansk State University were exposed to the virtual bioscreening using the Swiss Target Prediction software. The paper describes screening studies in vivo of 5 samples of sulfur-containing di- and tetrahydropyridines (laboratory codes d02-138, as-262, f02-079, cv-074, cv-143) in the standard hot plate test in comparison with the reference drug — metamizole sodium. The compounds in the dose of 5 mg/kg were given intragastrically 1 hour and a half before placing the rats on the hot plate, the reference drug in the dose of 7 mg/kg also was given intragastrically 1 hour and a half before placing the rats on the hot plate. The compounds with laboratory codes as-262 (allyl 6-({2-[(4-acetylphenyl)amino]-2-oxoethyl}thio)-5-cyano-4-(2-furyl)-2-methyl-1,4-dihydropyridine-3-carboxylate) and d02-138 (ethyl 4-[({[3-cyano-5-{[(2,4-dichlorophenyl)amino]carbonyl}-4-(2-furyl)-6-methyl-1,4-dihydropyridinе-2-yl]thio}acetyl)amino]benzoate) possess the most pronounced analgesic activity in the dose of 5 mg/kg, they demonstrated 2.03 and 1.9-fold efficiency in comparison to metamizole sodium respectively. The rest three specimens demonstrated metamizole sodium-like analgesic activity.

Surplus of sulfur produced as a by-product of oil refining and gas treatment as well as in the metallurgical industry makes it necessary to search for new areas of its application. It should be noted that the use of sulfur in the Arctic regions provides some undeniable advantages. Sulfur is not subject to corrosion during transportation and storage, and sulfur-based materials acquire specified design parameters as they cool down and do not require special temperature and humidity conditions. If the process temperatures are within 160°C, the complete environmental safety of the material is ensured, which excludes the potential emissions of toxic sulfur-containing compounds (hydrogen sulfide and sulfur dioxide).

In this study, a novel, easily prepared and stable acid-derived ionic liquid [DBUH]2[Cys] containing –S− anion was synthesized and used to catalyze the reactions of CO2 and epoxides. It was found that halogen-free IL could promote this kind of reactions under mild conditions, and high yields of cyclic carbonates were obtained. Moreover, [DBUH]2[Cys] could be reused at least five times without any obvious loss in catalytic activity. Compared with the common amino acid-derived ionic liquids, the –S− anion effectively promotes the catalytic activity of [DBUH]2[Cys], resulting in its high catalytic performance.

Here we describe a visible-light-induced, catalyst and additive-free approach for the [5 + 2] cycloadditions of vinylcyclopropanes (VCPs) with thioparabanates. This operationally simple strategy provides straightforward and atom-economic access to functionalized sulfur-containing seven-membered heterocycles, which bear two contiguous fully substituted stereogenic centers under mild reaction conditions.

The article discusses the main methods of capturing sulfur oxides in flue gases that are applicable at modern thermal power plants. The main products formed when burning organic fuel at thermal power plants are also considered.As a result of the oxidative reaction, the sulfur in organic fuel is converted into sulfur oxide; sulfur monoxide (SO), sulfur dioxide (SO2), and sulfur trioxide (SO3) are mostly formed. When released into the atmosphere with flue gases, these compounds have a negative impact not only on the elements of the heating unit, but also on the human body, flora and fauna. The conclusions present the main advantages and disadvantages of each method.