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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.

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.

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 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.

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.

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...

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

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).

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.

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.

Following the Deepwater Horizon (DWH) oil spill, the limited availability of the Macondo well oil prompted the use of a more widely available surrogate oil supplied by BP, collected from a nearby w...

The protective effectiveness of oil compositions in the presence of sulfur dioxide was studied. The moisture permeability of oil films and the corrosion rate of steels both protected and unprotected by oil films increase with increasing relative humidity and initial sulfur dioxide concentration in the atmosphere. The contribution of individual components to the protective effect of a film of synthetic Mobil-1 oil inhibited by the additive Emulgin in the presence of sulfur dioxide is considered. The total protective effectiveness of the system can reach 93-96% after one day in 0.5 M sodium chloride solution containing sulfur dioxide and the products of its interaction with water. The slowdown of steel corrosion under a layer of inhibited and non-inhibited oil film is mainly due to retardation of the cathodic process with slight inhibition of the anodic reaction.

Molecular characterization of sulfur-containing compounds in petroleum is of great significance for not only the oil refining but also geochemical application. One practical approach for the charac...

This review compiles and summarizes approaches to the preparation of heterocyclic systems containing sulfur atoms based on the reactions of disulfur dichloride which acts as an electrophilic reagent. It is shown that as a result of these transformations heterocycles with different numbers of sulfur atoms can be synthesized: 1,2,5-thiadiazoles, 1,2- and 1,4-thiazines, 1,2-dithiols, 1,2,3-dithiazoles, 1,2,3,4,5-pentathiepines, 1,2,3,4,5,6,7-heptathiocanes, and many others. The yields of the products of these reactions depend to a significant extent on the ratio of the reactants, the nature of the solvent, the base used, and the temperature. The exceptional role of disulfur dichloride in the synthesis of various sulfur-containing heterocycles is shown.

Изучено распределение электронной плотности 14 циклических соединений и одного нециклического. Проведен анализ зарядов и объемов групп, найдены группы доноры и акцепторы электронной плотности. Рассмотрено изменение электронной плотности серосодержащих групп под влиянием окружения. The electron density distribution of 14 cyclic compounds and one non-cyclic compound was studied. The group charges and group volumes were analyzed, and the electron density donor and acceptor groups were found. Changes in the electronic density of sulfur-containing groups under the influence of the environment are considered.

The research results of mine atmosphere normalization in potash mines are given.The method of mine air purification from toxic gases through ozonation is proposed. The developed technology of using photochemical method of neutralization hydrogen sulfide and methylmercaptan in mine atmosphere is described. Tests of the developed technology of neutralization sulfur compounds are conducted in mines of Upper reaches of the Kama river’s deposit of potassium and magnesium salts and the results are presented in this article. It is found out that installation of high pressure arc mercury lamps AML-400 for ozone generation on mining excavation machines allows to reduce sulfur gases concentration in workspace up to the level of maximum permissible.

A series of novel sulfur-containing cycliclipopeptides named thioamycolamides A-E, with thiazoline, thioether rings, and fatty acid moieties, were identified from the culture broth of the rare actinomycete Amycolatopsis sp. 26-4. The planar structural elucidation was accomplished by HRMS and 1D/2D NMR spectroscopic data analyses. The absolute configurations were unambiguously determined by Marfey's method, CD spectroscopy, and synthesis of partial structures. Moreover, their growth inhibitory activities against human tumor cell lines were investigated.

Naphtho[2,3b]thiophene is a linear sulfur containing polycyclic aromatic hydrocarbon. Naphtho[2,3b]thiophene and its derivatives are commonly accessed by a Bradsher cyclization. Synthesis of the Bradsher cyclization substrate typically requires harsh conditions, including several oxidation state changes. Here we report an improved, multigram synthesis of 3-bromonaphtho[2,3b]thiophene, exploiting a copper-catalyzed cross coupling to prepare the Bradsher substrate in 3 steps from commercial materials while minimizing redox reactions. Modification of the naphthothiophene scaffold in the 3-position has not previously been reported. In this work, the 3-bromonaphthothiophene is further functionalized via lithium-halogen exchange, with the key finding being a specific order of addition in lithiation is required to avoid undesired rearrangement reactions. A small yet versatile set of derivatives, including a naphthothiophene-containing chiral amine are prepared.

A formal CH2 -CH2 homologation conducted with C1 carbenoids on a carbon electrophile for the obtainment of a four-membered cycle is reported. The logic proposes the consecutive delivery of two single nucleophilic CH2 units to an isothiocyanate-as competent electrophilic partner-resulting in the assembling of a rare imino-thietane cluster. The single synthetic operation procedure documents genuine chemocontrol, as indicated by the tolerance to various reactive elements decorating the starting materials. Significantly, the double homologation protocol is accomplished directly on a carbon electrophile, thus not requiring the installation of heteroatom-centered manifolds (e.g. boron).

We demonstrated, that based on carvone, new symmetrical AA-type monomers with double bonds can be easily prepared by thiol-ene or Michael addition of dithiols. Moreover, hydrosilylation reaction wi...

The reaction mechanisms of sulfur-containing compounds in heavy oil in supercritical methanol were clarified. Four sulfur model compounds, namely n-hexyl sulfide, 3-methylthiophene, diphenyl sulfid...

Two flexible and colorless polymers are synthesized based on a phosphorus-containing derivative of a bio-based aromatic aldehyde (4-hydroxybenzaldehyde) by a thiol-ene reaction. Thanks to the high ...

With the aim of preparing of sulfur-containing derivatives of cymantrene, the hydrolysis of isothiouronium salts of alkylcymantrenes was studied under various conditions as well as subsequent chemical transformations of hydrolysis products. It was found that alkylcymantrenylthiols can be prepared either by hydrolysis of isothiouronium salts under the action of NaOH in a EtOH-acetone (4 : 1) mixture for 2 h or by the reduction of the corresponding disulfides by LiAlH4 formed in the course of this reaction in good yield for 6 h. Electrochemical properties of disulfides Cym(CHCH3)SS(CHCH3)Cym (Cym = C5H4Mn(CO)3) in solution before and after irradiation with a Hg lamp at λ365 nm were studied. The structures of the compounds were established by the X-ray analysis (CymCH(CH3)SSCH(CH3)Cym (I) (CIF file CCDC no. 1921952) and CymCH2SCH2Cym (II) (CIF file CCDC no. 1921953)).

Using a “chiral pool” approach, a number of chiral thiolate and sulfide ligands based on natural terpenes and terpenoids have been synthesized in a few simple steps. Two new Rh-thiolate com...

The luminescent heteroligand complexes of europium(III) with quinaldic acid and sulfur-containing neutral ligands Eu(Quin)3∙D∙3H2O (Quin–quinaldic acid, D–dimethyl sulfoxide or dihexyl sulfoxide) and Eu(Quin)3∙3H2O have been obtained. Their composition and structure have been determined. The thermal and spectral-luminescent properties of the heteroligand europium(III) complexes have been studied. The quinaldate ion has been found to coordinate to the europium(III) ion as a bidentate ligand. The Stark structure of 5D0–7Fj (j = 0, 1, 2) transitions in the low-temperature luminescence spectra of the europium(III) complexes has been analyzed

Acrylamide, a known neurotoxin, reproductive toxin, genotoxin, probable carcinogen, hepatotoxin, and immunotoxin, has sparked intense curiosity due to its prominent presence in thermally processed, carbohydrate-rich foods. Acrylamide formation occurs via the Maillard reaction at temperatures ≥100ºC. Thorough investigations on acrylamide mitigation through the application of sulfur-containing compounds to raw materials, and during food processing have been conducted. Although prominent results in acrylamide reduction have been observed, limitations are considered. These limitations involve the social and economic challenges of a population, such as the Caribbean. This study seeks to answer just how effective the application of sulfur-containing compounds is in reducing acrylamide exposure, especially when this applies to a developing region.

Studies of gold(III) ions sorption from hydrochloric acid solutions on 2,2‘-thiobisethanol dimethacrylate/ethylene glycol dimethacrylate copolymer were performed. The correlation between the concen...

Results are presented of the process of burning of sulfur-containing liquid fuels in a nonisothermal fluidized bed of a ShchKZ-1 industrial catalyst for the example of sulfurous and heavy high-sulfur oil. The optimal (“dropdown”) temperature profile in the bed was determined. This profile is characterized by a downstream decrease in temperature from 700 to 500°C. A mathematical simulation based on the description of experimental data on the variation of the sulfur concentration at the exit from the adsorbent (calcite) bed at its varied charge was used to calculate the specific capacity of the sorbent to be (14.2-15.9) x 103 g cm3. It was shown that the potential capacity of calcite in fluidized bed exceeds by an order magnitude that in a fixed bed.

Linear quinodimethane-embedded acene analogue 9L was synthesized, and its quinoidal structure was confirmed by X-ray crystallographic analysis. The multiple oxidation states of 9L could be achieved. Its dication is a triplet diradical, and its tetracation can be regarded as the isoelectronic structure of the nonacene, which was validated by experiments and theoretical calculations.

This article provides a brief overview of electrochemical potential-biological activity relationships of natural and synthetic cyclic sulfur-containing molecules against Steinernema feltiae, Botrytis cinerea, and Neuro 2a cell line (from murine neuroblastoma). This article finds natural cyclic sulfur-containing molecules and their synthetic analogues were more reducing than glutathione (GSH) and therefore apparently did not react with GSH. The nematicidal assay indicated that cyclic disulfide compound of 1 (3-vinyl-4H-1,2-dithiin, 1,2-VDT) was more active against Steinernema feltiae with the LD50 value 151.93 ± 1.3 μM, while dithiole thione group compounds showed moderate activity against this nematode. The article also finds compound 7 (3H-1,2-dithiole-3-thione or dithiolethione, DT) has a strong activity against all different strains of Botrytis cinerea in the range concentration of 0.1–0.5 mM. This article also finds that compounds 3 (1,2-dithiane, 1,2-DT), 4 (1,5-dithiacyclooctane, 1,5-DTCO), and 7 (3H-1,2-dithiole-3-thione or dithiolethione, DT) possess some moderate activity on Neuro 2a cell lines. Antinematode, antifungal, and anticancer activity of cyclic sulfur-containing molecules indicated that they could be promising candidates for “green pesticides” or phytoprotectans and for cancer prevention.

A simple and selective colorimetric method for detection of cysteine using chitosan stabilized gold nanoparticles has been developed. L-cysteine is a sulfur containing amino acid. Cysteine binds with the gold nanoparticles through a sulfur group and induces aggregation of the nanoparticles, which leads to a visible colour change from pale red to blue. A good linearity was observed from 0.1 to 30 μmol/L (R = 0.9958) cysteine, and the limit of detection was found to be 0.1 μmol/L. The gold nanoparticles showed a high selectivity towards the detection of cysteine even in the presence of 10 000 fold higher concentration of common interferences such as glutathione, methionine, and homocysteine. A plausible mechanism for the selective detection of cysteine in presence of interferences based on a dispersion–aggregation mechanism has been proposed.

International audience; With an estimated annual incidence of one million cases, leishmaniasis is one of the top five vector-borne diseases. Currently available medical treatments involve side effects, including toxicity, nonspecific targeting, and resistance development. Thus, new antileishmanial chemical entities are of the utmost importance to fight against this disease. We have shown in previous studies that gold(I) complexes bearing N-heterocyclic carbene (NHC) ligands with nitrogen- or sulfur-containing side arms have interesting biological activities in the field of cancer, malaria and leishmaniasis. The present study evaluates the in vitro antileishmanial effects on L. infantum axenic amastigotes and their cytotoxicity for the human THP1 cell line of a new family of six new imidazolium salts and their corresponding neutral (NHC)AuICl complexes. All new compounds have been characterized by classical analytical methods, and five gold complexes have been analyzed by X-ray structure determinations. We showed that one proligand has moderate activity (IC50 = 8.24 μM) while four of the six gold complexes have IC50 values in the low or sub μM range (0.15–1.3 μM), including three with selectivity index (SI) values between 46 and 108. These results suggest remarkable leishmanicidal activity in vitro for three new neutral (NHC)Au(I)Cl complexes, making them candidates for further in vivo studies, which are under investigation.