Chemistry
Luminescence Detection of Cr3+, Bi3+, and Acetone in Aqueous Solution by Core-Shell Tb-MOF
By using terephthalic acid 2 5-furandicarboxylic acid and terbium nitrate hexahydrate a Tb-MOF with a core-shell structure was successfully designed and prepared.
A one-pot method was employed to design and synthesize core-shell Tb-MOF. The morphology luminescence performance and stability were well characterized.
Tb-MOF demonstrated good water stability acid and alkali resistance and thermal stability. Tb-MOF was found to have high sensitivity to detect Cr3+ Bi3+ and acetone in an aqueous solution and the LOD of Cr3+ Bi3+ and acetone were calculated to be 0.18 μM 4.22 μM and 0.26% respectively. The sensing mechanism of Cr3+ and acetone was explained as energy-competitive absorption and the sensing mechanism of Bi3+ was explained as ion replacement.
The prepared Tb-MOF can be developed as a multifunctional light-emitting sensor with high selectivity.
Recent Advancement in the Development of Detection and Removal of Heavy Metal Ions by Deep Eutectic Solvents: A Review
Heavy metal pollution is one of the most serious environmental problems because of the non-degradable nature of heavy metals and their accumulation in the food chain which poses a severe threat to the environment and human health even at low concentrations. Most of these metal ions can coordinate with biological molecules and disturb their function. Exposure to heavy metals can cause different health threats such as endothelial dysfunction allergy infant mortality cancer neurological diseases respiratory diseases oxidative stress cardiovascular disorders and kidney diseases. Therefore the detection and removal of these toxic species are very important. Deep eutectic solvents (DESs) are green solvents and have excellent applications in many fields. They contain nonsymmetrical ions that have low lattice energy low vapor pressure dipolar nature non-flammability low volatility low melting points excellent thermal and chemical stability and high solubility. DESs are also better in terms of the availability of raw materials easy synthetic procedure low cost of their starting materials and their easy storage. DESs have an excellent ability for the detection and removal of heavy metal ions. In this review we discussed various DES-based spectrophotometric and fluorimetric chemosensors for the detection of heavy metal ions in different matrixes. Additionally we have also explored the capabilities of different DESs in removing heavy metals.
Recent Advancements in Biochar and its Composite for the Remediation of Hazardous Pollutants
Biochar has garnered considerable attention in recent times due to its potential uses in the environmental field. In this study we comprehensively examine and condense information on biochar production characteristics and adsorption mechanisms with a focus on its economic applications for remediating hazardous contaminants. Our assessment is based on over 200 publications from the past decade. Biochar a carbon-rich material can be derived from various organic waste sources such as food waste and urban sewage sludge. Researchers are particularly interested in biochar due to its high carbon content cation exchange capacity substantial specific surface area and stable structure. We investigate how the physical and chemical properties of biochar may vary based on the feedstock used providing a comprehensive overview of biochar and its composition for pollution remediation. The review also discusses common techniques such as gasification hydrothermal carbonization and pyrolysis used to produce biochar. We analyze current research on the mechanisms involved in pollutant treatment using biochar and its composites while also addressing future directions in biochar research.
Investigating the Effects of Urea-Zinc Sulfate-L Phenylalanine on the Corrosion Inhibition of Mild Steel Exposed to pH-4 Sulfuric Acid
Corrosion of mild steel is a risk to material and stability. The practice of corrosion inhibitors is a cost-effective corrosion modification method for mild steel. Organic inhibitors rich in electrons might have an excellent ability to prevent corrosion. This study aims to assess the inhibitory effect of the mixture of Urea Zinc Sulfate and L-Phenylalanine which has a high electron density.
MS corrosion was experimentally analyzed by dipping in H2SO4 solution at a pH – 4 for 24 hrs. Different gravimetric and conventional techniques such as polarization AC impedance AFM UV and fluorescence were used to examine the corrosion rate.
According to gravimetric measurements this combination produced 93% effective inhibition. The findings of the impedance test proved that the mixture of inhibitors that was adsorbed on the metal surface effectively prevented corrosion.
Likewise according to the Polarization measurements the inhibitor exhibits mixed-type performance with significant cathodic activity. UV Fluorescence and AFM findings showed that MS corrosion was suppressed because the inhibitor molecule adhered to the metal's surface and reduced.
Application of Time-of-flight Secondary Ion Mass Spectrometry in Lithium-ion Batteries
Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is becoming a powerful tool in the Lithium-Ion Batteries (LIBs) field due to its excellent resolution and sensitivity as well as its ability to provide spectrally and depth-resolved information. The perspective comprehensively delves into the application of ToF-SIMS in two major areas of LIBs research. Firstly the article elucidates how ToF-SIMS has been instrumental in deciphering the Solid Electrolyte Interphase (SEI) composition and analyzing electrolyte aging. The insights gleaned from such studies have paved the way for enhancing the longevity and safety of LIBs. Secondly we explore the role of ToF-SIMS in scrutinizing the distribution of interface reactions which are critical for understanding charge and discharge mechanisms. The analysis aids in optimizing the interface properties thereby improving battery performance. Such detections are paramount in ensuring the safety and operational stability of batteries. Overall the integration of ToF-SIMS in LIBs research offers a promising avenue for the development of advanced and safer energy storage systems.
Plastic Waste Valorization: Prospects for Green Hydrogen Production
Plastic waste is a current issue worldwide that is already negatively influencing and threatening the lives of human beings with residual micro- and nanoplastics entering water and soil bodies inducing recalcitrant pollution and health issues. The proposed perspective has been aimed to provide an overview of the potential of plastic waste valorization to green hydrogen and carbonaceous nanostructures. The overall concept additionally includes the utilization of the generated carbonaceous nanostructures to design advanced functional materials in combination with the obtained green hydrogen from plastic waste in a number of batch-to-flow catalytic hydrogenations to close the circle of sustainable integrated valorization of plastic waste. The concept also includes insightful Life-Cycle Assessment (LCA) and techno-economic studies in order to select the most relevant lines from the sustainability and cost-competitive standpoints.
Lactic Acid Bacteria As Biological Control Agent For Controlling Aspergillus Growth and Aflatoxin Production: A Review
Aspergillus sp. a ubiquitous filamentous fungus poses significant challenges to the food industry as a common spoilage and mycotoxin producing organism. The conventional use of chemical preservatives to control Aspergillus contamination raises concerns about potential health risks and environmental impacts. Therefore alternative approaches such as the utilization of natural biopreservatives as inexpensive safe and promising mycotoxin decontamination strategies are being explored. Lactic acid bacteria have gained considerable attention as potential candidates due to their antimicrobial properties and long-standing safe use in food fermentation. This review provides a thorough summary of the potential of lactic acid bacteria as biopreservatives against Aspergillus sp. The inhibitory mechanisms of lactic acid bacteria against the proliferation of Aspergillus and mycotoxin yield are explored highlighting the role of organic acids antimicrobial peptides and other bioactive compounds. The versatile application of lactic acid bacteria based natural preservatives across a range of food matrices storage conditions etc. is also addressed. Further research is warranted to optimize lactic acid bacteria strains explore synergistic combinations and investigate their efficacy in real food systems. Implementing lactic acid bacteria based biopreservative strategies could significantly enhance food safety and quality by reducing Aspergillus contamination and mycotoxin risks.
Carbon-Chalcogenide Cross-Coupling Reactions in Water
Over the past two decades researchers have witnessed the synthesis of diaryl sulfides and diaryl selenides via transition metals-mediated carbon-heteroatom cross-coupling reactions in the presence of various organic and inorganic solvents. The use of water as a clean and environmentally friendly solvent in cross-coupling chemistry of C-S/Se bond formations has attracted profound interest owing to its availability non-toxicity low cost and renewability. The most commonly used solvents have been recognized as being of environmental concern but the use of green and eco-friendly solvents like water is frequently considered with respect to the recovery of catalysts isolation of products and recycling. The fundamental interactions between the water and the transition metal catalysts or ligands are viewed from mechanistic aspects which mostly favours the rational selection of high-performance and safe solvents. In this article the authors intended to focus extensively on the critical role of water in various transition metals mediated C-S/Se cross-coupling methodologies.
Glycogen: A Novel Biopolymer Catalyst for the One-Pot Synthesis of Spirooxindoles, Spiro-Acenaphthylenes, and Spiro-2-Aminopyrans Derivatives under Mild Conditions
Glycogen a naturally occurring macromolecule in its granular form and without any post-modification was found to be an efficient and eco-friendly bifunctional heterogeneous organocatalyst.
This catalyst can be useful for the domino synthesis of various spiropyren annulated derivatives through three-component condensation of isathin malononitrile and diverse 13-dicarbonyl compounds activated CH-acids through Knoevenagel-Michael-annulation sequence under mild conditions.
Corresponding spiro derivatives were obtained in high to excellent yields after 5-15 min stirring in 2 mL EtOH and 60℃ in the presence of 0.01 g of glycogen equimolar amounts of isatin/acenaphthoquinone/ninhydrin malononitrile and 13-dicarbonyl compounds.
FTIR and 1H NMR spectroscopic showed there isn't any catalyst in the media and desired products were obtained in excellent purity.
Avoiding any transition metal one-pot and multicomponent procedure catalyzed by a biopolymer broad substrate scope and operational simplicity are essential features of this methodology for the preparation of medicinally important compounds.
A Review on Environment-friendly Protocol for the Synthesis of Pyrazole Derivative
Pyrazole derivatives are a significant group of heterocyclic compounds that have a diverse variety of biological activities and are used in several fields such as medicines agrochemicals and materials research. Conventional methods for synthesizing pyrazole derivatives typically require severe reaction conditions hazardous reagents and environmentally harmful solvents presenting considerable obstacles to achieving sustainable chemistry. This analysis specifically examines the latest progress made in creating environmentally friendly procedures for producing pyrazole derivatives. The study investigates different strategies in green chemistry such as reactions without solvents techniques including microwave and ultrasonic assistance and using renewable resources and environmentally friendly catalysts. An in-depth analysis is conducted to evaluate the efficiency selectivity and environmental impact of these approaches. This review intends to comprehensively explore the potential for sustainable practices in synthesizing pyrazole derivatives by emphasizing advancements in green synthetic methods. It seeks to encourage further research and use of green chemistry concepts in heterocyclic chemistry.
Selective Hydrogenation of Furfural into Cyclopentanone Over Composite Metal Catalysts under Mild Conditions
The direct hydrogenate conversion of furfural to cyclopentanone is very interesting technology in biomass conversion and utilization. Many kinds of metal catalysts were used in this field and composite metal catalysts exhibited superior catalytic performance. The hydrogenation process and rearrangement of the furan ring are competitive polymerization of furfural can prevent the improvement of yield for the main product.
Efficient and high selective catalyst need to be prepared for the improvement the yield of cyclopentanone from hydrogenate conversion of furfural under mild conditions.
Preparation of many composite metal catalysts and catalytic test for the direct hydrogenate conversion of furfural to cyclopentanone. Characterization is chosen to explore the strong metal synergistic effect and micro react mechanism.
MCM-41 was chosen as the carrier and both WO3 and TiO2 were selected as the modifiable assistant Ru-Cu-WO3@TiO2-MCM-41 were prepared successfully and performed a strong metal synergistic effect in this reaction. The 2%Ru-5%Cu-4%WO3@TiO2-MCM-41 exhibited a 98.54% yield of cyclopentanone when water was chosen as solvent and good stability was found in the recycle tests in mild conditions.
A certain amount of WO3 is helpful to enhance the Ru and Cu atoms’ dispersion and the number of acidic sites on the surface of nano catalyst which may weaken the cracking of C-C bonds and improved the yield of cyclopentanone in mild conditions. A certain amount of TiO2-anatase species adjusted the textural properties of the carrier and show good synergism catalytic function. The best catalytic hydrogenation conversion of furfural was high at 99.75% and the best selectivity to cyclopentanone was high at 98.79% over 2%Ru-5%Cu-4%WO3@TiO2-MCM-41 catalyst under mild conditions.
Substituted 4H-3,1-benzoxazine-4-one Derivatives as Inhibitors of Cathepsin G
Cathepsin G (CatG) is a cationic serine protease with a wide substrate specificity. CatG has been reported to play a role in several pathologies including rheumatoid arthritis ischemic reperfusion injury acute respiratory distress syndrome and cystic fibrosis among others.
We aim to develop a new class of CatG inhibitors and evaluate their potency and selectivity against a series of serine proteases.
We exploited chemical synthesis as well as chromogenic substrate hydrolysis assays to construct and evaluate the new inhibitors.
In this communication we report on a new class of CatG inhibitors of 4H-31-benzoxazin-4-one derivatives. We constructed a small library of seven substituted 4H-31-benzoxazin-4-one derivatives and identified their inhibition potential against CatG. Five molecules were identified as CatG inhibitors with values of 0.84-5.5 µM. Inhibitor 2 was the most potent with an IC50 of 0.84 ± 0.11 µM and significant selectivity over representative serine proteases of thrombin factor XIa factor XIIa and kallikrein.
Thus we propose this inhibitor as a lead molecule to guide subsequent efforts to develop clinically relevant potent and selective CatG inhibitors for use as anti-inflammatory agents.
In vitro and In vivo Biological Activity of Two Aryloxy-naphthoquinones in Mice Infected with Trypanosoma cruzi Strains
Chagas disease a condition caused by Trypanosoma cruzi is an endemic disease in Latin American countries that affects approximately eight million people worldwide. It is a continuing public health problem. As nifurtimox and benznidazole are the two pharmacological treatments currently used to treat it the present research proposes new therapeutic alternatives. Previous studies conducted on naphthoquinone derivatives have found interesting trypanocidal effects on epimastigotes with the molecules 2-phenoxy-14-naphthoquinone (IC50= 50 nM and SI < 250) and 2-(3-nitrophenoxy)-naphthalene-14-dione (IC50= 20 nM and SI=625) presenting the best biological activity.
The present study evaluated the efficacy of in vitro ex vivo and in vivo models of two aryloxyquinones 2-phenoxy-14-naphthoquinone (1) and 2-(3-nitrophenoxy)-naphthalene-14-dione (2) against two Mexican T. cruzi strains in both their epimastigote and blood Trypomastigote stage. Both compounds were evaluated against T. cruzi using a mouse model (CD1) infected with Mexican isolates of T. cruzi nifurtimox and benznidazole used as control drugs. Finally the cytotoxicity of the two compounds against the J774.2 mouse macrophage cell line was also determined.
The in vitro and in vivo results obtained indicated that both quinones were more active than the reference drugs. Compound 1 presents in vivo activity showing up to 40% parasite reduction after 8 h of administration a finding which is 1.25 times more effective than the results obtained using nifurtimox.
These are encouraging results for proposing new naphthoquinone derivatives with potential anti-T. cruzi activity.
Chemically Synthesized 1,2,3,4,6-Pentakis-O-Galloyl-β-D-Glucopyranoside Blocks SARS-CoV-2 Spike Interaction with Host ACE-2 Receptor
In the search for anti-COVID-19 therapy 12346-pentakis-O-galloyl-β-D-glucopyranoside a natural polyphenolic compound isolated from many traditional medicinal herbs has been reported as an RBD-ACE2 binding inhibitor and as a broad-spectrum anti-coronaviral inhibitor targeting the main protease and RNA-dependent RNA polymerase of SARS-CoV-2. To facilitate the structure-activity relationship studies of 12346-pentakis-O-galloyl-β-D-glucopyranoside we describe its chemical synthesis and characterization as well as its activity towards the SARS-CoV-2 spike interaction with host ACE2 receptor.
12346-Pentakis-O-galloyl-β-D-glucopyranoside was synthesized in two quantitative steps from 345-tribenzyloxybenzoic acid and β-D-glucopyranoside: DCC-mediated esterification and palladium-catalyzed per-debenzylation. The synthesized molecule was evaluated using a SARS-CoV-2 spike trimer (S1 + S2) ACE2 inhibitor screening colorimetric assay kit SARS-CoV-2 spike S1 RBD ACE2 inhibitor screening assay kit and a cellular neutralization assay using the Spike (SARS-CoV-2) Pseudotyped Lentivirus ACE2-HEK293 recombinant cell line.
The chemically synthesized product blocked the binding of the spike trimer of SARS-CoV-2 to the human ACE2 receptor with IC50=22±2 µM. It also blocked ACE2: spike RBD binding with IC50=27±3 µM. Importantly it inhibited the infectivity of SARS2-CoV2-Spike pseudotyped lentivirus on the ACE2 HEK293 cell line with IC50=20±2 µM.
Overall the chemically synthesized 12346-pentakis-O-galloyl-β-D-glucopyranoside represents a lead molecule to develop anti-SARS-CoV-2 therapies that block the initial stage of the viral infection by blocking the virus entry to the host cell.
N,N-Disubstituted 4-Sulfamoylbenzoic Acid Derivatives as Inhibitors of Cytosolic Phospholipase A2α: Synthesis, Aqueous Solubility, and Activity in a Vesicle and a Whole Blood Assay
Cytosolic phospholipase A2α (cPLA2α) is the key enzyme that initiates the arachidonic acid cascade through which pro-inflammatory lipid mediators can be formed. Therefore cPLA2α is considered an interesting target for the development of anti-inflammatory drugs. Although several effective inhibitors of the enzyme have been developed none of them has yet reached clinical application.
Recently we have prepared new 4-sulfamoylbenzoic acid derivatives based on a cPLA2α inhibitor found in a ligand-based virtual screening. The most effective of these compounds were now subjected to further variations in which the substitution pattern on the sulfamoyl nitrogen atom was changed.
The new compounds were tested in vitro in a vesicle assay for cPLA2α inhibition as well as for their water solubility metabolic stability and selectivity towards related enzymes. In addition they were evaluated ex vivo in a whole blood assay in which metabolites of the arachidonic acid cascade formed after activation of cPLA2α were quantified using a combined online dilution/online solid phase extraction HPLC-MS method.
Inhibitors with submicromolar inhibitory in vitro potency were found with favourable water solubility and selectivity. However their efficacy did not match that of the highly effective known structurally related cPLA2α inhibitor giripladib which was also tested as a reference. One advantage of some of the new compounds compared to giripladib was their significantly improved water solubility. When analyzing the substances in the ex vivo whole blood assay it was found that the obtained inhibition data correlated better with the in vivo results when the phorbol ester 12-O-tetradecanoylphorbol-13-acetate was used for activation of the enzyme in the blood cells instead of the calcium ionophore A23187.
New compounds with good activity towards cPLA2α and reasonable physicochemical properties were identified. Overall the results obtained could be helpful in the development of clinically applicable inhibitors of this enzyme.
Design, Synthesis and Evaluation of Antifungal Activity of Pyrazoleacetamide Derivatives
Fungal infections have posed a big challenge in the management of their treatment. Due to the resistance and toxicity of existing drug molecules in the light of pandemic infections like COVID-19 there is an urgent need to find newer derivatives of active molecules which can be effective in fungal infections.
In the present study we aimed to design pyrazole derivatives using molecular modeling studies against target 1EA1 and synthesize 10 molecules of pyrazole derivatives using a multi-step synthesis approach.
Designed pyrazole derivatives were synthesized by conventional organic methods. The newly synthesized pyrazole molecules were characterized by using FT-IR 1HNMR 13CNMR and LC-MS techniques. Molecular docking studies were also performed. The antifungal activity of newly synthesized compounds was assessed in vitro against Candida albicans and Aspergillus niger using the well plate method.
Two of the compounds OK-7 and OK-8 have been found to show significant docking interaction with target protein 1EA1. These two compounds have also been found to show significant anti-fungal activity against Candida albicans and Aspergillus nigra when compared to the standard fluconazole. The Minimum Inhibitory Concentration (MIC) value of these two compounds has been found to be 50 µg/ml.
Pyrazole derivatives with -CH3 CH3O- and -CN groups have been found to be active against tested fungi and can be further explored for their potential as promising anti-fungal agents for applications in the field of medicinal chemistry.