Organosulfur Research Articles

Ameliorating Effect of S-Allyl Cysteine (Black Garlic) on 6-OHDA Mediated Neurotoxicity in SH-SY5Y Cell Line

Therapeutic approaches based on isolated compounds derived from natural products are more common in preventing diseases involving inflammation and oxidative stress at present. S-allyl cysteine (SAC) is a promising garlic-derived organosulfur compound with many positive effects in cell models and living systems. SAC has biological activity in various fields, enclosing healing in learning and memory disorders, neurotrophic effects, and antioxidant activity. In this study, we purposed to identify the neuroprotective activity of SAC toward 6-OHDA-induced cell demise in the SH-SY5Ycell line. For this purpose, 6-OHDA-induced cytotoxicity, and biochemical, and gene expression changes were evaluated in SH-SY5Y cells. SH-SY5Y cells grown in cell culture were treated with SAC 24hours before and after 6-OHDA application. Then, cell viability, antioxidant parameters, and gene expressions were measured. Finally, immunofluorescence staining analysis was performed. Our results showed that SAC increased cell viability by 144% at 80µg/mL with pre-incubation (2hours). It was observed that antioxidant levels were significantly increased and oxidative stress marker levels were decreased in cells exposed to 6-OHDA after pre-treatment with SAC (p<0.05). SAC supplementation also suppressed the increase in pro-inflammation levels (TNF-α/IL1/IL8) caused by 6-OHDA (p < 0.05). While 8-OHdG and Nop10 expressions were observed at a mild level in SAC pretreatment depending on the dose, 8-OHdG, and Nop10 expressions were observed at a moderate level in SAC treatment after 6-OHDA application (p<0.05). Our findings demonstrate the positive effect of pretreatment with SAC on SH-SY5Y cells injured by 6-OHDA, suggesting that SAC may be beneficial for neuroprotection in regulating oxidative stress and neuronal survival in an in vitro model of Parkinson's disease.

Enhanced super-ultra-deep photocatalytic oxidative desulfurization by titanium-activated metal-organic frameworks nanophotocataltyst

Addressing the escalating global demand for fossil fuels and the urgent environmental concerns associated with their use necessitates the development and implementation of efficient and cost-effective techniques for the removal of sulfur compounds. In this study, titanium-activated MIL-101(Fe) was utilized for the removal of organosulfur compounds through the photocatalytic oxidation desulfurization (PODS) process. The coexistence of active sites with titanium and iron resulted in an ultra-deep desulfurization. The impact of titanium loading was assessed, with TxML representing the ratio of Ti to Fe (x = 1, 1.5, and 2, respectively). Nanophotocatalysts were fabricated by solvothermal method. The physicochemical properties of the new materials were investigated by performing XRD, TEM, FT-IR, FESEM, EDX, UV–Vis DRS, PL, GC–MS, ESR, TGA, transient photocurrent, and nitrogen adsorption–desorption analyses. The effect of titanium loading on the structure, and performance of photocatalysts in the PODS reaction was investigated. The reaction parameters were optimized for maximum efficiency. Under optimal conditions of T2ML loading at 1.5 g/L, a volumetric solvent to fuel ratio (S/F) of 1, and a temperature of 50 ℃, T2ML shows the best performance by removing 100 % of dibenzothiophene.Kinetic experiments revealed that the PODS reaction obeys a pseudo-first order equation, and activation energy is 47.08 kJ.mol−1.

Alliaceae versus Brassicaceae for Dyslipidemia: State of the Art and Future Perspectives. Systematic Review and Meta-Analysis of Clinical Studies.

Dyslipidemia is a risk factor for cardiovascular diseases. Preclinical studies have shown that organosulfur compounds from the Alliaceae and Brassicaceae plants, such as garlic (Allium sativum L.) and broccoli (Brassica oleracea L.), have potential lipid-lowering effects. However, their clinical efficacy is controversial, especially in "drug-free" patients. The aim of this work was to summarize evidence on the lipid-lowering properties of extracts containing organosulfur compounds in patients with dyslipidemia. Studies were searched in four databases (Medline, Scopus, Embase, and CENTRAL), from inception to October 11, 2023.Controlled clinical studies on patients with dyslipidemia receiving Alliaceae or Brassicaceae were included. The outcome was the change in lipid parameters from baseline. Random-effect meta-analysis of the extracted data was performed using R software. The effect size was expressed as mean difference (MD) and 95% confidence interval (CI). The certainty of evidence was assessed with the GRADE approach. Out of 28 studies that were reviewed, 22 were included in the meta-analysis (publication period: 1981-2022). Results showed that Alliaceae extracts significantly reduce total cholesterol [MD: -15.2 mg/dL; 95% CI: -21.3; -9.1] and low-density lipoprotein cholesterol levels [MD: -12.0 mg/dL; 95% CI: -18.1; -5.7], although with low certainty of evidence. Conversely, the lipid-lowering properties of Brassicaceae extracts are still unexplored. Our results support the use of Alliaceae extracts in patients with hypercholesterolemia, but future high-quality studies are needed. Our work suggests further exploration of the efficacy of Brassicaceae extracts, which may have high nutraceutical/phytotherapeutic potential, opening new perspectives in the management of dyslipidemia.

Using benzonaphthothiophenes to trace paleo-oil migration directions in the Ediacaran-Cambrian reservoirs of the central Sichuan Basin

Benzonaphthothiophenes (BNTs) are important organosulfur compounds in oil, and their concentrations and [2,1]/([2,1] + [1,2])BNT ratio have been used as migration tracers. Here we focus on the applicability of BNTs as migration tracers for abnormally heat-altered paleo-oil reservoirs. For this purpose, 57 pyrobitumen samples from the Ediacaran to Cambrian dolomite reservoirs in the central Sichuan Basin were collected and detected by gas chromatography-mass spectrometry. The results showed that most pyrobitumens of the studied samples are characterized by high concentrations of unsubstituted polycyclic aromatic hydrocarbons (PAHs), high values of fluoranthene/PAHs, pyrene/PAHs, fluoranthene/(fluoranthene + pyrene), benzofluoranthene/(benzofluoranthene + benzopyrene), and unsubstituted-to-methylated aromatic ratios due to the alteration by abnormal heating. These pyrobitumens have high concentrations of BNTs, and their three isomers show a pattern of [2,1] > [1,2] > [2,3]BNT. The BNTs concentrations display a good positive relationship with the concentrations of the abnormal heating-related PAH, while [2,1]/([2,1] + [1,2])BNT ratio has no correlation with the abnormal heating-related indices, suggesting that abnormal heating of the paleo-oil reservoirs lead to the enrichment of BNTs but has a limited effect on [2,1]/([2,1] + [1,2])BNT ratio. Moreover, [2,1]/([2,1] + [1,2])BNT ratio seem to be not affected by kerogen type and depositional environment, but increases with source rock maturity. Therefore, the [2,1]/([2,1]+[1,2])BNT is still an effective migration tracer for abnormally heated reservoirs. This ratio was applied as migration tracer in the studied area. The result suggests that the paleo-oil primarily migrated from west depression to east bulges, followed by the direction from northwest to southeast, which is congruent with the geological setting and exploration practice, demonstrating the applicability of this parameter for abnormally heat-altered oil reservoirs.

Adsorption Desulfurization of Simulated Diesel Fuel Using Graphene Oxide

Graphene oxide (GO) was synthesized from graphite powder by the improved Hammers method and used for the adsorption of organosulfur compound (dibenzothiophene, DBT) from model diesel fuel. FT-IR spectroscopy, X-ray diffraction, SEM, EDX, and BET were used to characterize the GO. Several factors, such as solution pH, initial DBT concentration, adsorption contact time, adsorption temperature, and adsorbent dosage were used to test the DBT removal efficiency. The results show that the maximum removal was 96.4% at pH = 5, initial solution concentration of 200 ppm, adsorption time of 45 min, temperature of 45C and adsorbent dosage of 0.4 g/25 mL.

Experimental study of hydrogen sulfide (H2S) behavior in brine/n-decane mixtures under HPHT conditions

This research investigates the dynamic behavior of hydrogen sulfide (H2S) under oil reservoir conditions, focusing on their interplay within both aqueous and organic phases. Surprising findings emerge, notably the heightened solubility of H2S at 250°C compared to 150°C, with values of 19.9 mg to 41.5 and 12.8 mg to 16.4 mg in 100ml of solution, respectively, diverging from conventional expectations, due to organosulfur compounds generated at the water/n-decane interface under high pressure and temperature conditions. Through an examination of Henry's Law and the calculation of Henry's constants across several temperatures, insights into these observations are gained. In the organic phase, temperature is observed to catalyze the formation of organosulfur compounds from n-decane and H2S. Notable compounds identified include aromatic hydrocarbons bearing sulfur substituents. highlighting the presence of 2-Propyldibenzothiophene (2 – 392 mg/mL), which represents between 57 and 95% of the total concentration of organosulfur compounds found in the organic fraction, being more abundant at 250°C. These findings underscore the intricate interplay between temperature, pressure, and phase composition, elucidating the nuanced solubility patterns and reaction dynamics of sulfur and organosulfur compounds.

Photoperiod and temperature as dominant environmental drivers triggering chemical compositions of garlic bulb during growth

Photoperiod and temperature are crucial for plant growth and development, but the accumulation patterns and regulatory mechanisms of garlic in response to these factors remain unclear. Compared to normal conditions (12/12 h light/dark; 22/15 °C day/night), increasing the photoperiod by 1 h each month with normal temperature (13/11, 14/10, 15/9, 16/8 h; light/dark; 22/15 °C day/night) or increasing photoperiod by 1 h with a 1.5 °C increase in temperature (13/11, 14/10, 15/9, 16/8 h light/dark; 23.5/16, 25/17, 26.5/18, 28/19 °C day/night) at monthly intervals substantially affects garlic growth in early G204, mid-G666, and late G390 harvest cultivars. For both increased photoperiod and temperature, the environment most favorable for bulb growth is characterized by the maximum accumulation of hormones (IAA, JA, and ZT) during bulb formation, while higher levels of ACC, phenolic acids, and organosulfur compounds are observed during the harvesting stage. Furthermore, the accumulation patterns of alliin and allicin in garlic bulbs for G204, G666, and G390 cultivars significantly increased, with fold changes of (2.0, 1.8, and 1.9) and (1.8, 1.7, and 1.5), respectively, in response to increased photoperiod and temperature conditions. Additionally, the accumulation pattern in G204, and G666 was similar but notably distinct from late harvest G390 during growth. In this study, metabolomics models were constructed to assess chemical composition variations and predict the differences among three garlic varieties during the growth stages. These models revealed functional component variations and provided reliable predictions, offering valuable insights for estimating garlic chemical compositions and identifying optimal environmental conditions for growth.

Photoredox-Catalyzed Phosphine-Mediated Successive Deoxygenation of Sulfonyl Oxime Salts Enables Anti-Markovnikov Hydrothiolation of Alkenes.

Stable and easy-to-handle sodium salts of sulfonyl oximes were first identified to proceed via visible-light-driven phophine-mediated successive deoxygenation to realize the anti-Markovnikov hydrothiolation of alkenes, which could serve as an odorless sulfur source. Mechanistic studies revealed that the key thiyl radical intermediate could be generated in situ from the sulfonyl oxime anion via a phosphine-mediated fragmentation and a sequential deoxygenation process. Notably, a wide range of alkenes, including acrylamides, acrylates, vinyl ketones, vinyl sulfones, and acrylonitriles, are competent substrates for this protocol, which is highly beneficial for the construction of structurally diversified organosulfur compounds.

Synergistic Effects of Ethanol Extract of Allium sativum (Garlic) with DAPT and ATRA on Notch Signaling Targeted Molecular Action on Lung Cancer Cell line (A549)

Background: The activated oncogenic Notch signalling is an emerging target to treat cancer progression and recurrence. Synthetic inhibitors of Notch receptors are in pre-clinical studies. However, the overexpression of Notch signalling molecules at the gene level needs to be regulated to control cancer progression. Objective: We propose that this can be achieved by gene-regulatory drugs in combination with natural phytochemical compounds. Methods: The ethanol extract of Allium sativum alone and in combination with DAPT and ATRA were evaluated for cytotoxicity on A549 cells by MTT and Trypan blue assays. Their effects on Notch 1, Hes 1 and p53 gene expressions were studied by RT-PCR and qPCR. Their inhibition on metastatic invasion of A549 cells was analyzed by in vitro wound scratch assay. The phytochemicals of the extract were identified by GC-MS analysis. Results: Many organosulfur compounds having anti-cancer potency were identified in GC-MS. The combination treatment with 50μg (IC50) of garlic extract exhibited a highly significant (P≤0.01) synergistic inhibitory effect on A549 cell growth and migration. It has also significantly reduced the expression of Notch 1 and Hes 1 oncogenes and enhanced p53 gene expression, compared with the individual treatments. This indicates the synergistic action of the extract on the downregulation of Notch signalling at the mRNA level. Conclusion: Our study results imply that the combination therapies have potent molecular treatment action via down-regulating Notch signaling target genes and upregulating p53 gene expression as an underlying mechanism of inhibitory action on A549 lung cancer cells.

Emerging Trends for the Direct Synthesis of Dithiocarbamates

Dithiocarbamates are common structural motifs in various bioactive compounds, attracting considerable attention due to their wide‐ranging applications in organic synthesis, material science, agrochemicals, and the pharmaceutical industry. Given the significant bioactivity and extensive applications of dithiocarbamates, the continuous pursuit of their efficient and diverse synthetic methods remains critical and urgent. Direct dithiocarbamation reactions can introduce ‐S‐C(S)NR2 group directly into parent molecules, providing shorter, greener, and more practical pathways for the synthesis of organodithiocarbamates. This article offers a comprehensive overview of the latest advancements in direct dithiocarbamation reactions, categorizing them based on the different sources of the ‐S‐C(S)NR2 group, with a particular emphasis on elucidating substrate scope and reaction mechanisms. Additionally, some synthetic limitations and applications of these methods are discussed. This review aims to provide the latest advancements in this field to both general readers and professional practitioners, inspiring innovative ideas for the synthesis of organosulfur compounds.

Click Chemistry for the Generation of Combination of Triazole Core and Thioether Donor Site in Organosulfur Ligands: Applications of Metal Complexes in Catalysis.

During the last two decades, organosulfur compounds have been used in the field of transition metal catalysis. Some of such compounds are known for their ability to withstand their exposure to air and moisture. These compounds are very important ligands. They may be obtained using simple and smooth modular synthetic protocols which include nucleophilic substitution reactions. The development of click chemistry represents a new era of innovation. It is a lighthouse of reliable and efficient reactions. In recent past, click chemistry has also been applied for the synthesis of such organosulfur ligands specifically suited for the dynamic field of transition metal catalysis. In order to synthesize novel compounds containing sulfur and triazole ring, click chemistry is an advantageous methodology over other approaches. This article covers the general features and uses of this methodology for the development of catalytically active organosulfur compounds. The significant advances in the design of transition metal catalytic systems utilizing such ligands, their use in the catalysis of many chemical transformations are also covered in this article. Effort has also been made to present a comparative overview of the performances of such catalysts vis-à-vis the catalysts designed commonly used ligands. Catalytic performances have been discussed thoroughly in order to identify the impact of ligand architecture on efficacy of the catalyst. Effect of reaction conditions (such as time, temperature etc.) and mechanistic aspects have also been rationalized.

Sustained use of antimutagenic bioactives having affinity with DNA minor groove could prevent in vitro neoplastic induction

IntroductionStudies on the antimutagenic and anti-neoplastic effect of dietary ingredients can be useful in developing nutraceuticals for preventing neoplastic induction. In the current study the query whether food rich in antimutagenic potential equally suppress the neoplastic induction, was addressed, with potential mechanism of action. MethodsThe antimutagenic activity was evaluated using the TK6 gene mutation assay, assessing the reduction in ethyl methanesulfonate (EMS)-induced mutation in presence of vegetable extracts. The anti-⁠neoplastic activity was assessed using the C3H/⁠10T1/⁠2 cell transformation assay, quantifying the inhibition of anchorage-independent growth and type III foci formation. The prominent compounds in the vegetable extract were characterised using gas chromatography-⁠mass spectrometry (GC-⁠MS), and their interactions with DNA were predicted using molecular docking. ResultsAmong the vegetable extracts, garlic exhibited the most potent antimutagenic and anti-neoplastic effects, followed by spinach and beans. Garlic extract exhibited significantly high antimutagenic potential (59±3%), and anti-neoplastic activity in the terms of inhibition of anchorage independence (65±3%) and inhibition of type III foci formation (90±5%). GC-MS analysis of garlic extract identified abundant organosulphur compounds, terpenes, and terpenoids. Molecular docking studies suggested that these compounds bind to the DNA minor groove with binding energies ranging from −⁠4.3 to −⁠7.21 kcal mol-⁠1. DiscussionThe antimutagenic and antineoplastic activities showed a positive correlation (r=0.92–0.93), where garlic extract showed the highest potential. The DNA binding properties of the prominent compounds in garlic extract suggests a potential mechanism of action involving interference with carcinogen activity and subsequent prevention of gene dysregulation.

Advances in Functional Organosulfur-Based Mediators for Regulating Performance of Lithium Metal Batteries.

Rechargeable lithium metal batteries (LMBs) are promising next-generation energy storage systems due to their high theoretical energy density. However, their practical applications are hindered by lithium dendrite growth and various intricate issues associated with the cathodes. These challenges can be mitigated by using organosulfur-based mediators (OSMs), which offer the advantages of abundance, tailorable structures, and unique functional adaptability. These features enable the rational design of targeted functionalities, enhance the interfacial stability of the lithium anode and cathode, and accelerate the redox kinetics of electrodes via alternative reaction pathways, thereby effectively improving the performance of LMBs. Unlike the extensively explored field of organosulfur cathode materials, OSMs have garnered little attention. This review systematically summarizes recent advancements in OSMs for various LMB systems, including lithium-sulfur, lithium-selenium, lithium-oxygen, lithium-intercalation cathode batteries, and other LMB systems. It briefly elucidates the operating principles of these LMB systems, the regulatory mechanisms of the corresponding OSMs, and the fundamentals of OSMs activity. Ultimately, strategic optimizations are proposed for designing novel OSMs, advanced mechanism investigation, expanded applications, and the development of safe battery systems, thereby providing directions to narrow the gap between rational modulation of organosulfur compounds and their practical implementation in batteries.

Evaluation of the Biostimulant Activity and Verticillium Wilt Protection of an Onion Extract in Olive Crops (Olea europaea).

The olive tree is crucial to the Mediterranean agricultural economy but faces significant threats from climate change and soil-borne pathogens like Verticillium dahliae. This study assesses the dual role of an onion extract formulation, rich in organosulfur compounds, as both biostimulant and antifungal agent. Research was conducted across three settings: a controlled climatic chamber with non-stressed olive trees; an experimental farm with olive trees under abiotic stress; and two commercial olive orchards affected by V. dahliae. Results showed that in the climatic chamber, onion extract significantly reduced MDA levels in olive leaves, with a more pronounced reduction observed when the extract was applied by irrigation compared to foliar spray. The treatment also increased root length by up to 37.1% compared to controls. In field trials, irrigation with onion extract increased the number of new shoots by 148% and the length of shoots by 53.5%. In commercial orchards, treated trees exhibited reduced MDA levels, lower V. dahliae density, and a 26.7% increase in fruit fat content. These findings suggest that the onion extract effectively reduces oxidative stress and pathogen colonization, while enhancing plant development and fruit fat content. This supports the use of the onion extract formulation as a promising, sustainable alternative to chemical treatments for improving olive crop resilience.

Organosulfur Compounds, S-Allyl-L-Cysteine and S-Ethyl-L-Cysteine, Target PCSK-9/LDL-R-Axis to Ameliorate Cardiovascular, Hepatic, and Metabolic Changes in High Carbohydrate and High Fat Diet-Induced Metabolic Syndrome in Rats.

Metabolic syndrome (MetS) is an ever-evolving set of diseases that poses a serious health risk in many countries worldwide. Existing evidence illustrates that individuals with MetS have a 30%-40% higher chance of acquiring type 2 diabetes mellitus (T2DM), cardiovascular disease (CVD), or both. This study was undertaken to uncover the regulatory role of natural organosulfur compounds (OSCs), S-allyl-L-cysteine (SAC), and S-ethyl-L-cysteine (SEC), in targeting high carbohydrate high fat (HCHF)-diet-induced MetS-associated risk management. Our findings suggested that SAC and SEC ameliorated HCHF-diet-induced diabetic profiles, plasma lipid and lipoprotein level, liver function, oxidative-stress, inflammatory cytokines, and chemokines including monocyte chemoattractant protein-1 (MCP-1), lipid peroxidation, plasma proprotein convertase subtilisin/kexin type-9 (PCSK-9), and high-sensitivity C-reactive protein (hs-CRP). Moreover, the assessment of the hepatic mRNA expression of the key genes involved in cholesterol homeostasis depicted that SAC and SEC downregulated the PCSK-9 mRNA expression via targeting the expression of HNF-1α, a transcriptional activator of PCSK-9. On the other hand, the LDL-receptor (LDL-R) expression was upregulated through the activation of its transcriptional regulator sterol regulatory element binding protein-2 (SREBP-2). In addition, the activity and the mRNA expression of 3-hydroxy-3-methylglutaryl coenzyme-A reductases (HMG-R) and peroxisome proliferator-activated receptors (PPARs) were also improved by the treatment of SAC and SEC. We concluded that SAC and SEC can protect against MetS via improving the lipid and lipoprotein content, glycemic indices, hepatic function, targeting the inflammatory cascades, and oxidative imbalance, regulation of the mRNA expression of PCSK-9, LDL-R, SREBP-2, HNF-1α, PPARs, and inflammatory biomarkers.

Phytochemicals, Two New Sulphur Glycosides and Two New Natural Products, from Shepherd's Purse Seed and Their Activities.

Two new sulfur glycosides, bursapastoris A-B (3-4), were extracted and isolated from shepherd's purse seed, along with two new natural products, 11-(methylsulfinyl)undecanoic acid (2) and 10-(methylsulfinyl)decanoic acid (1). Their structures were determined though infrared spectroscopy, one-dimensional nuclear magnetic resonance (1H and 13C), and electrospray ionization mass spectrometry. Additionally, the structures of 3-4 were further identified by two-dimensional nuclear magnetic resonance (HMBC, HSQC, 1H-1H COSY, and NOESY). Compounds 1-4 showed relatively favorable docking to NF-κB. Unfortunately, we only discovered that compound 1-4 had weak anti-radiation activity at present. Therefore, further research regarding the biological activity of these organosulfur compounds is required at a later stage.

Alliaceae-Derived Supplementation Improves the Severity of COVID-19 Symptoms among Elderly Nursing Home Residents.

This study investigates the effect of daily consumption of a concentrated garlic and onion extract on COVID-19 symptoms among elderly nursing home residents. Volunteers consumed a daily capsule of the concentrated powder rich in organosulfur compounds over 36 weeks during lunch. The incidence and severity of COVID-19 symptoms between the treatment and control groups were compared, along with monitoring the safety of consumption, incidence of other diseases, and medicine usage. The treatment group showed a significant reduction in both the number and severity of COVID-19 symptoms compared to the control group, with no significant adverse effects observed. No significant reduction in symptom duration was detected. This study provides preliminary evidence that concentrated garlic and onion extract may aid in the treatment of COVID-19 among older adults. These findings suggest potential public health benefits, emphasizing the need for further research to explore the immunomodulatory properties of these natural compounds.

Untargeted metabolite profiling of Aggregatum onion cultivars: Insights from GC-MS based metabolomics studies

Allium cepa, commonly known as onion, is renowned for its culinary and medicinal properties. This article investigates the phytochemical composition of four aggregatum onion varieties using preliminary phytochemical screening and gas chromatography-mass spectrometry (GC-MS) analysis. The study reveals diverse metabolites, including hydrocarbons, aldehydes, terpenoids, and organosulfur compounds, with variations observed among the onion varieties. Significant proportions of compounds such as diisooctyl phthalate, hexanol, and nobilitin, possessing various pharmacological activities like antimicrobial and antioxidant properties, were identified. The research emphasizes the importance of understanding onion phytochemistry, particularly given its widespread cultivation and consumption, notably in regions like Tamil Nadu, India. The identified bioactive compounds shed light on different onion varieties’ unique attributes and potential health benefits. By elucidating onion bulb metabolite profiles using advanced techniques like GC-MS, this study contributes to understanding the phytochemical diversity within Allium cepa species. These findings lay the groundwork for future research into the medicinal and nutritional advantages of onions and support targeted breeding (selective breeding) programs to enhance health-promoting compounds in onion varieties. Overall, this study underscores onions’ significance as a culinary staple and a valuable source of diverse bioactive compounds with pharmacological potential.

Eco-Friendly Functionalization of Ynals with Thiols under Mild Conditions.

A new eco-friendly method for the synthesis of mono- and multifunctional organosulfur compounds, based on the process between ynals and thiols, catalyzed by bulky N-heterocyclic carbene (NHC), was designed and optimized. The proposed organocatalytic approach allows the straightforward formation of a broad range of thioesters and sulfenyl-substituted aldehydes in yields above 86%, in mild and metal-free conditions. In this study, thirty-six sulfur-based derivatives were obtained and characterized by spectroscopic methods.

Efficient electrochemical degradation of ranitidine by a novel Bi-coated titanium oxide electrode: Performance and mechanism

Ranitidine (RAN) is a commonly prescribed medication that poses ecological risks due to its potential to transform into the carcinogenic byproduct N-nitrosodimethylamine (NDMA) in the environment. Herein, we synthesized a novel bismuth-coated titanium oxide (Bi-Ti4O7) electrode using a straightforward coating method and evaluated its effectiveness in the electrochemical oxidation of RAN. The Bi-Ti4O7 electrode achieved a degradation efficiency of 90.41 % for an initial RAN concentration of 10 mg/L within 120 min, greatly outperforming the pristine Ti4O7 electrode. The incorporation of Bi enhances the oxygen vacancies and charge transfer characteristics, facilitating direct electron transfer between RAN and the Bi-Ti4O7 electrode. The potential degradation pathways of RAN by the Bi-Ti4O7 electrode included C–S bond cleavage, C–N bond cleavage, and electrophilic oxidation. No NDMA was generated during the oxidation process, and the toxicity of RAN oxidation intermediates was greatly reduced. The Bi-Ti4O7 electrode demonstrated excellent stability, maintaining over 90 % degradation efficiency across 30 cycles, and showed wide applicability across different pH levels and wastewater types with negligible Bi ion release (0.148 µg/L). These results underscore the potential of Bi-Ti4O7 as an effective and sustainable solution for RAN-polluted wastewater treatment.