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The nitrogen-and oxygen-rich azole-based high energetic compound 3,3′-(2-(trinitromethyl)-2H-1,2,3-triazole-4,5-diyl)-bis(1,2,4-oxadiazole) (5) was synthesized from a readily accessible bis-cyano-substituted-azole in three steps with an overall good yield. The reaction sequence was even successful on the gram scale. The five-membered azole backbone with a –C(NO2)3 group contributes to boosting energetic properties of the molecule. The synthesized compounds were fully characterized using NMR, IR, HRMS, and TGA–DSC studies. X-ray diffraction analysis established the molecular topology of the desired compound. The molecule showed promising energetic performance with a good oxygen balance (−31.6%), high positive heat of formation (+679.8 kJ mol−1), and high detonation pressure (P = 29.6 GPa) and velocity (Dv = 8356 m s−1), which are close to those of PETN, superior to those of HNS, and surpass those of TNT. Hirshfeld surface analysis gives insights into the molecule's sensitivity. [ABSTRACT FROM AUTHOR]

In this study, NiO-added NiCo 2 O 4 composite samples were prepared using three distinct synthesis methods to study the impact of synthesis technique and NiO addition on the electrochemical performance of NiCo 2 O 4. The chosen methods, sol-gel, co-precipitation, and ultrasonication, represent a range of approaches that yield different particle structures and morphologies. The structural and morphological studies of composite samples were investigated using X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM), respectively. XRD analysis revealed the crystalline composition, revealing the presence of two distinct phases: NiO and NiCo 2 O 4. The Rietveld analysis of the composite samples supports the dual phases in the samples. FESEM analysis confirms the change in size and shape of the particles with the synthesis procedure. Optical properties, measured via UV–visible absorbance spectra, demonstrated that the energy gap varied with the synthesis method. The sol-gel samples exhibited the highest energy gap at 2.20 eV. The magnetic properties were measured using the vibration sample magnetometer (VSM), and the results confirm that the synthesis procedure influences magnetic loops and coercivity. The electrochemical performance of the samples in a 3 M potassium hydroxide electrolyte revealed that the co-precipitation method produced the highest capacitance of 398 Fg-1 at a 10 mV/s sweep rate, indicating superior energy storage capacity compared to pure NiCo 2 O 4. Adding NiO phase to the NiCo 2 O 4 matrix is believed to enhance electrochemical performance by creating additional charge at the grain boundaries, leading to a synergistic effect and improved electron and ion transport. The exceptional electrochemical performance of these composite materials suggests that the synthesis methods and the addition of NiO play a critical role in determining the overall efficiency and applicability of battery-type supercapacitors. These findings pave the way for further research into optimizing synthesis parameters to enhance energy storage capacity and inspire the development of advanced spinel metal oxide composite electrodes for supercapacitors and other energy storage applications. [ABSTRACT FROM AUTHOR]

Three oxorhenium(V) complexes [ReOLCl2(PPh3)] (C1–C3) were synthesized in the reaction of 2,3‐pyridinedicarboxylic acid (HL1), 2,5‐pyridinedicarboxylic acid (HL2), and 2,6‐pyridinedicarboxylic acid (HL3) with [ReOCl3(PPh3)2]. Chemical structures of synthesized compounds were confirmed using standard analytical techniques. The most stable geometry of complexes was proposed using density functional theory calculations. The antiproliferative activity of the synthesized complexes was evaluated in a panel of human tumor cell lines (A549, PANC‐1, OVCAR‐3, and MDA‐MB‐231) and in one nontumor cell line (MRC‐5), in comparison with the activity of cisplatin as a reference drug. The complex C3 exhibited the highest antiproliferative potential in PANC‐1 cells, with IC50 48.73 ± 0.31 μM. Our previous research of oxorhenium(V) complexes suggested the involvement of drug‐efflux transporter P‐glycoprotein (Pgp) in the detoxification of rhenium complexes in pancreatic adenocarcinoma cells. In the present study, the effect of verapamil hydrochloride, the specific pharmacological blocker of Pgp, was tested in combination with novel rhenium complexes C1–C3 or cisplatin (CDDP), in PANC‐1 cells. The verapamil enhanced the antiproliferative activity of complex C3, indicating again the role of Pgp in detoxification of oxorhenium(V) complexes in highly invasive and resistant PANC‐1 cells. [ABSTRACT FROM AUTHOR]

In this study, we introduce a novel porous metal–organic framework named Co2(bbda)2(DMF)2·5H2O, or MOF‐UoR‐1, synthesized via hydrothermal techniques employing a unique Schiff base ligand. The framework underwent comprehensive characterization, confirming its microporous nature through gas‐sorption measurements. MOF‐UoR‐1 demonstrated remarkable efficacy as a catalyst for the one‐step synthesis of pyrimidine analogs. Structural validation of the synthesized pyrimidines was accomplished via 1H‐nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) analyses. Through systematic experimentation, the optimal catalyst dosage (40 mg) was determined, showcasing its effectiveness across various aldehydes, 1,3‐carbonyl compounds, and urea substrates. Noteworthy is the broad applicability of this environmentally friendly protocol, which offers advantages such as high yields (96%), rapid reaction times (90 min), straightforward product isolation, and product purity without necessitating column chromatography. Furthermore, the catalytic integrity of the framework remained intact, enabling its reuse without compromising performance. This research presents a promising approach for the synthesis of pyrimidine derivatives, with significant implications for sustainable and efficient chemical synthesis methodologies. [ABSTRACT FROM AUTHOR]

In the present study, a composite composed of resin containing imidazole-GMA resin and a natural filler of silk powder (IGMSP) was used as an alternative to bisphenol A-glycidyl methacrylate (Bis-GMA) dental composites. Dental composite was prepared by both optical and thermal polymerizations. FTIR, 1HNMR spectroscopy, and FESEM-EDX were used to identify the structure and morphology of the synthesized compounds. Thereafter, the thermal properties, water sorption and solubility, and anti-cancer and antibacterial activities of the composite were investigated. The structure of Imidazole-GMA resin as well as the successful surface modification of the filler with Si–O groups were confirmed with 1HNMR and FTIR spectra. Due to the use of natural filler of silk powder, the thermal resistance of the composite was found to be relatively low. The water adsorption and solubility of composite were lower than Bis-GMA. The results of antibacterial properties and cytotoxicity of the composite were much promising due to the presence of imidazole components in the resin structure. This composite was shown to have a significant inhibitory effect on MCF7 cells (IC50 = 11.4 µM, Maximum inhibitory effect 94.68%), and it was proved that Imidazole-GMA has significant effects on all three gram-negative (IZD 27–35 mm) and three gram-positive (IZD 22–29 mm) bacterial species. [ABSTRACT FROM AUTHOR]

Astaxanthin is a naturally occurring xanthophyll with powerful: antioxidant, antitumor, and antibacterial properties that are widely employed in food, feed, medicinal and nutraceutical industries. Currently, chemical synthesis dominates the world's astaxanthin market, but the increasing demand for natural products is shifting the market for natural astaxanthin. Haematococcus pluvialis (H. pluvialis) is the factory source of natural astaxanthin when grown in optimal conditions. Currently, various strategies for the production of astaxanthin have been proposed or are being developed in order to meet its market demand. This up-to-date review scrutinized the current approaches or strategies that aim to increase astaxanthin yield from H. pluvialis. We have emphasized the genetic and environmental parameters that increase astaxanthin yield. We also looked at the transcriptomic dynamics caused by environmental factors (phytohormones induction, light, salt, temperature, and nutrient starvation) on astaxanthin synthesizing genes and other metabolic changes. Genetic engineering and culture optimization (environmental factors) are effective approaches to producing more astaxanthin for commercial purposes. Genetic engineering, in particular, is accurate, specific, potent, and safer than conventional random mutagenesis approaches. New technologies, such as CRISPR-Cas9 coupled with omics and emerging computational tools, may be the principal strategies in the future to attain strains that can produce more astaxanthin. This review provides accessible data on the strategies to increase astaxanthin accumulation natively. Also, this review can be a starting point for new scholars interested in H. pluvialis research. [ABSTRACT FROM AUTHOR]

BACKGROUND: To investigate the recovery of molybdate from water and hydrodesulfurization catalysts, a novel synthesized phosphonate Schiff base, 4,4′‐(((2,2‐dimethylpropane‐1,3‐diyl) bis(azaneylylidene)) bis(methaneylylidene)) bis(2‐methoxyphenol) (HMI) and 4‐(((3‐((4‐(((S)‐hydroxyhydrophosphoryl)oxy)‐3‐methoxybenzylidene) amino)‐2,2‐dimethylpropyl)imino)methyl)‐2‐methoxyphenyl hydrogen phosphonate (HIMP), was utilized. This study aimed to assess the structural and property aspects of this synthesized compound using diverse characterizations, including FTIR, Thermogravimetric Analysis (TGA), mass spectrometry (GC–MS), fluorescence transfer spectra, scanning electron microscopy (SEM), and 1H‐NMR, 13C‐NMR, and 31P‐NMR. RESULTS: The study systematically examined several factors controlling molybdate recovery, including temperature, adsorbent dosage, pH, interaction time, and molybdate concentration using the batch technique. Optimal sorption effectiveness was achieved at pH 2, with an interaction time of 40 min, a 0.06 g adsorbent dose, at ambient temperature. The newly devised adsorbent exhibited an impressive adsorption capacity (Qe) of 372.54 mg of Mo per gram, with empirical data fitting the Langmuir and D‐R adsorption models. The kinetics of molybdate uptake followed second‐order kinetics. Thermodynamic aspects, including ΔG°, ΔS°, and ΔH°, were also investigated, providing appreciated perceptions into the energetic dynamics of the sorption process. Additionally, molybdate adsorption in the occurrence of other ions was explored, highlighting the selectivity of the modified phosphonate Schiff base for molybdate removal. CONCLUSION: The study underscores the potential of the modified phosphonate Schiff base as a crucial adsorbent for molybdate elimination from both solutions and spent hydrodesulfurization catalysts. The findings offer important insights into the adsorption kinetics, thermodynamics, and selectivity of the adsorbent, enhancing our understanding of molybdate recovery processes and their broader applications. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Green synthesis represents a superior strategy for mitigating the adverse effects of chemical synthesis on the environment. In particular, the utilization of bio-sourced materials for nanomaterial synthesis constitutes a more sustainable and environmentally sound alternative. In this study, silver–carbon particle (Ag-CP) nanocomposites were prepared by a green hydrothermal method using lily bulbs as raw materials and were employed for glucose detection. Through the use of various physical characterization techniques, it was demonstrated that the natural lily hydrothermal method yielded carbon particles that were modified with Ag nanoparticles. The electrochemical characteristics of the Ag-CP nanocomposites for glucose sensing were investigated using cyclic voltammetry and chronoamperometry. The results showed that the constructed glucose sensor was capable of detecting concentrations within the range of 1–11 mM (R2 = 0.998), with sensitivity of 203.56 μA mM−1 cm−2 and a detection limit of 76.6 μM (S/N = 3). The Ag-CP nanocomposite sensor also exhibited notable electrocatalytic activity and remarkable anti-interference capability. In light of the exceptional sensing performance, coupled with the straightforward and cost-effective preparation process, the development of nanocomposite materials employing naturally sourced biological materials represents an attractive avenue for the production of eco-friendly nanocomposites. [ABSTRACT FROM AUTHOR]

The electrochemical coupling of biomass oxidation and nitrogen conversion presents a potential strategy for high value‐added chemicals and nitrogen cycling. Herein, in this work, CuO/Co3O4 with heterogeneous interface is successfully constructed as a bifunctional catalyst for the electrooxidation of 5‐hydroxymethylfurfural to 2,5‐furandicarboxylic acid and the electroreduction of nitrate to ammonia (NH3). The open‐circuit potential spontaneous experiment shows that more 5‐hydroxymethylfurfural molecules are adsorbed in the Helmholtz layer of the CuO/Co3O4 composite, which certifies that the CuO/Co3O4 heterostructure is conducive to the kinetic adsorption of 5‐hydroxymethylfurfural. In situ electrochemical impedance spectroscopy further shows that CuO/Co3O4 has faster reaction kinetics and lower reaction potential in oxygen evolution reaction and 5‐hydroxymethylfurfural electrocatalytic oxidation. Moreover, CuO/Co3O4 also has a good reduction effect on NO3−. The ex‐situ Raman spectroscopy shows that under the reduction potential, the metal oxide is reduced, and the generated Cu2O can be used as a new active site for the reaction to promote the electrocatalytic conversion of NO3− to NH3 synthesis. This work provides valuable guidance for the synthesis of value‐added chemicals by 5‐hydroxymethylfurfural electrocatalytic oxidation coupled with NO3− while efficiently producing NH3. [ABSTRACT FROM AUTHOR]

SUMMARY Erianin, crepidatin, and chrysotobibenzyl are typical medicinal polymethoxylated bibenzyls (PMBs) that are commercially produced in Dendrobium species. PMBs' chemo‐diversity is mediated by the manifold combinations of O‐methylation and hydroxylation in a definite order, which remains unsolved. To unequivocally elucidate the methylation mechanism of PMBs, 15 possible intermediates in the biosynthetic pathway of PMBs were chemically synthesized. DcOMT1–5 were highly expressed in tissues where PMBs were biosynthesized, and their expression patterns were well‐correlated with the accumulation profiles of PMBs. Moreover, cell‐free orthogonal tests based on the synthesized intermediates further confirmed that DcOMT1‐5 exhibited distinct substrate preferences and displayed hydroxyl‐group regiospecificity during the sequential methylation process. The stepwise methylation of PMBs was discovered from SAM to dihydro‐piceatannol (P) in the following order: P → 3‐MeP → 4‐OH‐3‐MeP → 4‐OH‐3,5‐diMeP → 3,3'(4′),5‐triMeP → 3,4,4′,5‐tetraMeP (erianin) or 3,3′,4,5‐tetraMeP (crepidatin) → 3,3′,4,4′,5‐pentaMeP (chrysotobibenzyl). Furthermore, the regioselectivities of DcOMTs were investigated by ligand docking analyses which corresponded precisely with the catalytic activities. In summary, the findings shed light on the sequential catalytic mechanisms of PMB biosynthesis and provide a comprehensive PMB biosynthetic network in D. catenatum. The knowledge gained from this study may also contribute to the development of plant‐based medicinal applications and the production of high‐value PMBs. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD), a neurodegenerative condition is expected to affect 152 million in 2050. The current study comprises the evaluation of thiazole based thiadiazole bearing sulfonamide derivatives to treat Alzheimer's disease. A series of compounds (1‐15) were synthesized and were studied for their anti‐Alzheimer's potential. Their IC50 values lie in the range between (19.20±0.20 nM–2.50±0.20 nM) for AChE and (19.80±0.20 nM–3.30±0.50 nM) for AChE. Among all of them, analog 2, 7, 9, and 15 were reported to possess significant activity. Among all the members of series, compound 15 having IC50=2.50±0.20 nM and 3.30±0.50 nM for AChE and BuChE, respectively, emerged as the most promising candidate due to the presence of two electronegative fluorine (F) atoms. The small and highly electronegative fluorine atoms have the ability to block the enzyme's activity by forming strong hydrogen bonds with the amino acids of the target enzymes, thereby inhibiting their function. The efficacy of these novel compounds was studied in comparison to the standard drug donepezil having IC50=5.80±0.30 nM for AChE and IC50=6.30±0.81 nM BuChE. For further assessment of inhibition potential and mode of inhibition, molecular docking study of all the potent compounds was carried out. Further, the structural identity of the synthesized compounds was confirmed using various spectroscopic techniques, including 1H‐NMR, 13C‐NMR, and High‐Resolution Electron Impact (HREI) Mass spectrometry, which provided detailed information about their molecular structure. ADME analysis of all the synthesized compounds confirmed their potential as drugs, indicating favorable pharmacokinetic properties and a promising drug profile. [ABSTRACT FROM AUTHOR]

Synthesis of novel (E)‐N‐(4‐(substituted)benzylidene)‐6‐substituted‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamides/carboxamides was achieved by the condensation of 6‐substituted‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamides/carboxamides with substituted benzaldehydes in alcoholic medium in the presence of acetic acid. The structures of synthesized compounds are assigned on the basis of FT IR, 1H NMR, 13C NMR and Mass Spectral data. The compounds are subjected for their antibacterial, antifungal and DFT studies. Compounds, (E)‐6‐chloro‐N‐(4‐(dimethylamino)benzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamide (5 b), (E)‐6‐chloro‐N‐(4‐(dimethylamino)benzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carboxamide (5 f), and (E)‐6‐chloro‐N‐(4‐hydroxybenzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carboxamide (5 j) possessed pronounced antibacterial and antifungal activities due to their chemical structure. [ABSTRACT FROM AUTHOR]

We report hereby a sensitive and rapid label free colorimetric assay of two amino acids, viz. L -arginine (L -Arg) and L -cysteine (L -Cys), through silver sol synthesized via a wet chemical method using 2-boronobenzoic acid (2- BBA) as a reducing and capping reagent in an aqueous alkaline medium. 2-BBA was synthesized in situ by the reaction of 2-formylphenylboronic acid (2-FBPA) and silver nitrate through Tollen's method. The as-synthesized silver sol exhibited the formation of nanocubes having their most predominant size in the range of 20–25 nm upon their TEM scanning and exhibiting an SPR band at 401 nm in their UV-vis spectrum. The same were further characterized by SEM, EDX, AFM, FTIR, XPS, DLS, and zeta potential measurements also. Separate interaction of the two amino acids, viz., L -Arg and L -Cys, with diluted AgNCs (1 : 2; AgNCs and Millipore water V/V) exhibited two different colors, pinkish grey and blue, respectively accompanied by distinctive shifts in their surface plasmon resonance (SPR) band also. The detection limits were found to be 6 μM and 3 μM for L -Arg and L -Cys respectively. Furthermore, L -Arg and L -Cys were quantified in a pharmaceutical sample each with their respective recovery rates of 99.2% and 90.1%. These AgNCs exhibited rich SERS characteristics also by intensifying the Raman peaks of L -Arg and L -Cys. Only a few one-pot aqueous chemical syntheses of silver nanocubes have been reported previously. Most probably, this is the third report of its kind. To the best of our knowledge, no silver nanoprobe exhibiting simultaneous detection of L -Arg and L -Cys has been reported to date. [ABSTRACT FROM AUTHOR]

A new series of N-benzyl-2,5-dihydro-1H-pyrrole-linked benzopyrimidines 5 and 6 were synthesized via the 1,3-dipolar cycloaddition reaction of acetylenic dipolarophiles 3 and 4 with azomethine ylide generated in situ from N-(methoxymethyl)-N-(trimethylsilyl)benzylamine and evaluated for their in vitro antimicrobial activity. The structures of the prepared products were characterized using 1H/13C NMR, IR, and ESI-HRMS techniques. Further, the synthesized compounds were assessed for their antibacterial activity against five types of pathogenic bacteria and three fungal strains. The results show that the degree of antimicrobial effect displayed by the synthesized compounds was variable. Notably, compounds 2a, 2d, 2f, 3e, 3h, 4a, 4d, 4f, 5a, 5b, 5d, 5f, 6b, and 6c showed high activity against the bacterial strains, with MIC values ranging from 15.12 to 15.62 μg mL−1. Moreover, compounds 2a, 2f, 5a, 5b, 5d, 5g, and 5h exhibited promising antifungal activity against three Candida strains, with MIC values ranging from 62.5 to 125 μg mL−1. In addition, molecular docking studies performed to identify the most effective antibacterial compounds against B. subtilis highlighted the high binding affinity of the synthesized compounds toward Bacillus subtilis YdiB (pdb: 5MVR). [ABSTRACT FROM AUTHOR]

A series of pyridyl‐substituted nitronyl nitroxides was synthesized and structurally characterized. A comprehensive magnetochemical and quantum chemical study of extended raw of the nitroxides with different substituents R in the pyridine fragment was performed. It was shown, that temperature‐dependent magnetic properties are determined by the short contacts between nitroxide groups of adjacent molecules as well as between nitroxide group and methyl substituents in the pseudo axial positions of imidazoline fragments. Quantum chemistry allows to select the appropriate model of exchange cluster for analysis of experimental magnetic data and evaluation of the exchange interaction parameters. For NN–PyCl the "order‐disorder" transition was detected by means of low temperature XRD. The difference in the experimental and calculated exchange interaction energies may serve as an indicator of temperature‐induced structural rearrangements. For instance, for methyl substituted nitronyl nitroxide NN‐PyMe structural transformations and significant changes in exchange interaction energies were observed. [ABSTRACT FROM AUTHOR]

Comprehensive Summary The conversion of aniline to nitrosobenzene (NSB), a key step in the synthesis of important chemicals, demands the development of environmentally friendly photocatalysts that operate under mild conditions. This process is driven by the need for sustainable methods, given toxic nature of aniline and its central role in the production of dyes, pharmaceuticals, and agricultural chemicals. This study reports on the synthesis of three reduced phosphomolybdate compounds with Co(II) centers and polypyridine ligands, which show great potential as photocatalysts for the mild oxidation of aniline to NSB. The synthesis uses 30% H2O2 as the oxidant and the compounds as the sole catalysts, achieving high conversion rates and selectivity without additional additives or photosensitizers. The integration of multidentate ligands with {P4Mo6} clusters significantly reduces the band gap, facilitating visible‐light‐driven photocatalysis. The adsorption interaction between coordinated water molecules and Co ions and H2O2 is found to enhance the conversion rate of aniline, a finding supported by DFT analyses. [ABSTRACT FROM AUTHOR]

ABSTRACT In our work, we have successfully synthesized twelve diorganotin(IV) complexes (4–15) from different hydrazone ligands and diorganotin(IV) dichlorides. The complexes have a general formula [R2SnL1–3], where R = Et, Me, Bu, and Ph groups. The hydrazone ligands (1–3) were synthesized through a condensation reaction involving 3‐ethoxysalicylaldehyde with different benzhydrazide derivatives. All the synthesized hydrazone ligands and their complexes underwent screening by employing numerous spectroscopic and physicochemical techniques, such as molar conductance measurements, mass spectrometry, (1H, 119Sn, and 13C) NMR, SEM‐EDAX, and FT‐IR. Spectroscopic analysis revealed that the hydrazone ligands were attached to tin atoms in a tridentate fashion via ONO donor atoms, suggesting a pentacoordinated geometry for the complexes. Furthermore, the X‐ray crystallography analysis for Complex 6 revealed the distorted square pyramidal geometry around the tin atom. Moreover, a DFT study was also carried out for Ligand 3 and its complexes (12–15) by employing B3LYP/LanL2DZ theory level (Gaussian 9 software package) to obtain the optimized geometry and global reactivity descriptors, structural behavior, and their efficacy against different microbes. To assess the biological efficacy of synthesized compounds, an in vitro antimicrobial assay was conducted against different fungal (Aspergillus niger and Candida albicans) and bacterial (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa) strains. The results of the antimicrobial assay demonstrated that Complexes 7, 11, and 15 depicted better results against E. coli strain and C. albicans strain, implying that the higher lipophilic character of these complexes facilitates their easy passage through the cell membrane of microbes. Furthermore, an ADMET study was carried out to evaluate the toxicity score of synthesized compounds. [ABSTRACT FROM AUTHOR]

Efficient catalytic methods that allow the use of simple and abundant chemical feedstocks for the preparation of synthetically versatile compounds are central to modern synthetic chemistry. Acetylene is a basic feedstock with a remarkable production over one million tons per year, although it is underutilized in the stereoselective synthesis of fine chemicals. Here we report a facile catalytic multicomponent reaction that allows for the enantio‐ and diastereoselective allylboration of acetylene gas. This process is catalyzed by a chiral copper catalyst, operates without specialized equipment or pressurization, and provides chiral skipped dienes bearing stereodefined and orthogonally functionalized olefins with excellent levels of chemo‐, regio‐, enantio‐ and diastereoselectivity. The combined stereochemical features and orthogonal functionalization make the products privileged structural scaffolds to access the complete set of stereoisomers of the chiral skipped diene core through simple enantio‐ and diastereodivergent pathways. The utility of the method is demonstrated with the enantioselective synthesis of three bioactive natural skipped diene products, namely (+)‐Nyasol, (+)‐Hinokiresinol and Phorbasin C, and other related synthetically relevant chiral molecules. [ABSTRACT FROM AUTHOR]

Proteoglycans (PGs), consisting of glycosaminoglycans (GAGs) linked with the core protein through a tetrasaccharide linkage region, play roles in many important biological events. The chemical synthesis of PG glycopeptides is extremely challenging. In this work, the enzymes required for synthesis of chondroitin sulfate (CS) PG (CSPG) have been expressed and the suitable sequence of enzymatic reactions has been established. To expedite CSPG synthesis, the peptide acceptor was immobilized on solid phase and the glycan units were directly installed enzymatically onto the peptide. Subsequent enzymatic chain elongation and sulfation led to the successful synthesis of CSPG glycopeptides. The CS dodecasaccharide glycopeptide was the longest homogeneous CS glycopeptide synthesized to date. The enzymatic synthesis was much more efficient than the chemical synthesis of the corresponding CS glycopeptides, which could reduce the total number of synthetic steps by 80 %. The structures of the CS glycopeptides were confirmed by mass spectrometry analysis and NMR studies. In addition, the interactions between the CS glycopeptides and cathepsin G were studied. The sulfation of glycan chain was found to be important for binding with cathepsin G. This efficient chemoenzymatic strategy opens new avenues to investigate the structures and functions of PGs. [ABSTRACT FROM AUTHOR]

Glycine derivatives are prevalent structural motifs that can be easily found in many bioactive molecules and natural isolates. To date, chemical synthesis of hydrazino-containing glycine derivatives has mainly focused on the utilization of metal catalysts or light-irradiation methods. Herein, we report a three-component reaction of amines, azodicarboxylates, and diazoalkanes under green and sustainable reaction conditions, leading to a wide range of hydrazino-containing glycine derivatives in good to excellent yields. Compared to the reported methods, the as-developed method does not require catalysts or light irradiation. The success of the scale-up reaction, synthetic transformation of the formed glycine products, and the direct aqueous media synthesis further rendered the method attractive and valuable. Control experiments together with detailed mechanism studies revealed that the in situ formed diaziridines are the key reaction intermediates. [ABSTRACT FROM AUTHOR]

This study focuses on the development of regiospecific hydroarylation polyaddition of naphthalene‐ and carbazole‐based monomers with diynes under mild reaction conditions at room temperature. A 1‐pyrazole substituent serves as an appropriate directing group for a Co‐catalyst to efficiently activate the C–H bonds of generally inactive six‐membered aromatic hydrocarbons. The 1‐pyrazole groups in 2,6‐di(1‐pyrazolyl)naphthalene adopt planar conformations and act as directing groups, resulting in a smooth hydroarylation reaction. In contrast, the reaction with 1,5‐di(1‐pyrazolyl)naphthalene do not proceed. The polyaddition reaction of 2,6‐di(1‐pyrazolyl)naphthalene selectively proceeds at 3,7‐positions under mild reaction conditions at 30 °C, and yields corresponding poly(arylenevinylene) (PAV) with high molecular weight. This molecular design is also applicable to the hydroarylation polyaddition of carbazole; the polyaddition reaction of 9‐(2‐ethylhexyl)‐3,6‐di(1‐pyrazolyl)carbazole selectively occurred at 2,7‐positions. The optical and electronic properties of the synthesized compounds are evaluated. The obtained PAVs serve as an emitting material in organic light‐emitting diode (OLED). This study aims to develop a Co‐catalyzed hydroarylation polyaddition via C–H activation of generally inactive polyaromatic hydrocarbons (PAHs) under mild conditions. [ABSTRACT FROM AUTHOR]

Chemical reactivity and applications of 4-alkynylated pyrazol-3-ones are described. A facile access to the synthesis of novel pyrazol-4-yl furan- and/or thiophene-2-carboxylates through the ring transformation and subsequent acylation of 4-alkynylated pyrazol-3-ones as the key intermediates, which were prepared from pyrazole-4,5-dione and terminal alkynes, in moderate to good yields is achieved. All the synthesized compounds were characterized by spectroscopic analysis. [ABSTRACT FROM AUTHOR]

The stereodivergent synthesis of all four stereoisomers of diethyl 4-hydroxyphosphopipecolate from the commercial chiral building block ethyl (R)-4-cyano-3-hydroxybutanoate is described. Key steps in the synthesis of the target compounds involve the triethyl phosphite nucleophilic addition to chiral N -acyliminium ion easily obtained from (R)-4-hydroxypiperidin-2-one, giving diethyl (2 R ,4 R)- and (2 S ,4 R)-4-hydroxyphosphopipecolate diastereoisomers, easily separable by column chromatography followed by the 4-hydroxy epimerization through a sequential oxidation and highly diastereoselective reduction strategy, affording the diethyl (2 R ,4 S)- and (2 S ,4 S)-4-hydroxyphosphopipecolate, respectively, consistent with our recently found results. All synthesized compounds were thoroughly characterized. [ABSTRACT FROM AUTHOR]

Unstable tetra(methoxycarbonyl)cyclopentadienone was investigated in the synthesis of electron-deficient cycloheptatrienes via [4+2]-cycloaddition/cycloelimination reaction with cyclopropenes. The use of its stable dimer did not afford the product although similar reactions with alkynes have been reported. Quantum chemical calculation revealed that cyclopentadienone is not generated from the dimer and the reaction with alkynes proceeds via a more complicated cycloelimination/cycloaddition/cycloelimination cascade. However, the formation of cycloheptatrienes was found favorable over the formation of the dimer. Therefore, the trapping of tetra(methoxycarbonyl)cyclopentadienone upon formation was successful to give cycloheptatrienes with five ester groups. The use of methyl coumalate as a four-electron component was successful with cyclopropenes containing only one ester group to afford only two ester groups in the product. [ABSTRACT FROM AUTHOR]

The selective conversion of unsaturated compounds has emerged as a crucial method in chemical synthesis, enabling the synthesis of functional organic molecules. In recent decades, transition metal‐catalyzed hydrosilylation has emerged as a highly successful exemplar of industrialization within the realm of organic chemistry for the production of organosilanes, which have a pivotal role in organic chemistry and materials science. Precious metal complexes are typically employed as catalysts in most industrial hydrosilylation processes. The exploration of Earth‐abundant alternatives has emerged as a focal point of considerable research attention due to the high cost, poor selectivity, and many side reactions reported for precious metal catalysts. Ligand skeleton construction, selectivity, and mechanism research are areas where cobalt catalysts have more potential than iron and nickel. This review discusses the recent advances in cobalt‐catalyzed hydrosilylation across carbon‐carbon, carbon‐oxygen, and carbon‐nitrogen multiple bonds from 2019 to 2023. [ABSTRACT FROM AUTHOR]

Monogalactosyldiacylglycerol (MGDG), a predominant photosynthetic membrane lipid derived from plants and microalgae, has important applications in feed additives, medicine, and other fields. The low content and various structural stereoselectivity differences of MGDG in plants limited the biological extraction or chemical synthesis of MGDG, resulting in a supply shortage of monogalactosyldiacylglycerol with a growing demand. Herein, we established Saccharomyces cerevisiae as a cell factory for efficient de novo production of monogalactosyldiacylglycerol for the first time. Heterologous production of monogalactosyldiacylglycerol was achieved by overexpression of codon-optimized monogalactosyldiacylglycerol synthase gene MGD1, the key Kennedy pathway genes (i.e. GAT1, ICT1, and PAH1), and multi-copy integration of the MGD1 expression cassette. The final engineered strain (MG-8) was capable of producing monogalactosyldiacylglycerol with titers as high as 16.58 nmol/mg DCW in a shake flask and 103.2 nmol/mg DCW in a 5 L fed-batch fermenter, respectively. This is the first report of heterologous biosynthesis of monogalactosyldiacylglycerol in microorganisms, which will provide a favorable reference for study on heterologous production of monogalactosyldiacylglycerol in yeasts. [ABSTRACT FROM AUTHOR]

In this work, we have reported the design, synthesis, in vitro, and in silico enzymatic evaluation of new bis-4-hydroxycoumarin-based phenoxy-1,2,3-triazole-N-phenylacetamide derivatives 5a-m as potent α-glucosidase inhibitors. All the synthesized analogues showed high inhibition effects against α-glucosidase (IC50 values ranging between 6.0 ± 0.2 and 85.4 ± 2.3 µM) as compared to the positive control acarbose (IC50 = 750.0 ± 0.6 µM). Among the newly synthesized compounds 5a-m, 2,4-dichloro-N-phenylacetamide derivative 5i with inhibition effect around 125-folds more than the acarbose was identified as the most potent entry. A structure–activity relationship (SAR) study about the title compounds 5a-m demonstrated that the inhibition effects of these compounds depend on the pattern of substitution on the N-phenylacetamide ring. The interaction modes and binding energies in the active site of enzyme of the important analogues (in term of SAR study) were evaluated through molecular docking study. Molecular dynamics and prediction of pharmacokinetic properties and toxicity of the most potent compound 5i also evaluated and the obtained data was compared with the acarbose. [ABSTRACT FROM AUTHOR]

ABSTRACT In recent times, there has been a growing exploration of transition metal complexes as potential solutions for significant health challenges, including tuberculosis, microbes infection, and inflammation. Therefore, in our ongoing effort to identify biologically effective agents, Co(II), Ni(II), Cu(II), and Zn(II) metal complexes of H2L1–H2L2 hydrazone ligands were synthesized. The structural features of synthesized compounds were recognized by employing several techniques such as FT‐IR, 1H NMR, 13C NMR, powder x‐ray diffraction (XRD), UV‐Vis, ESR, TG‐DTA, mass spectrometry, and molar conductance measurements. The bonding of ligands via Ophenolic, Oenolic, and Nazomethine donor atoms and the attachment of the three water molecules with metal ion to form the octahedral structure of complexes were corroborated by different spectroscopic techniques. The anti‐tuberculosis, antimicrobial, and anti‐inflammatory activities of the synthesized compounds were assessed using the microplate alamar blue assay, serial dilution, and bovine serum albumin (BSA) methods, respectively, and highlighted the more potency of the complexes than ligands. The synthesized Cu(II) (9) and Zn(II) (10) metal complexes exhibited excellent ability to inhibit the growth of H37Rv strain of Mycobacterium tuberculosis in comparison to standard drug streptomycin. The Cu(II) (6 and 9) and Zn(II) (10) complexes showed superb ability as antimicrobial agents, whereas Cu(II) (5) and Zn(II) (6) complexes exhibited significant anti‐inflammatory ability. The in vitro findings on the antituberculosis activity were reinforced by a significant molecular docking study, which has become a crucial component of computational research utilizing the enzyme Mtb Pks13 thioesterase domain of M. tuberculosis. Additionally, in this research work, the absorption–distribution–metabolism–excretion–toxicity (ADMET) study sparked the compounds' drug‐like behavior. [ABSTRACT FROM AUTHOR]

This study investigates organotin (IV) complexes derived from the recently synthesized quinazoline Schiff base ligand (L). The research involves synthesizing and characterizing these complexes, including elemental analysis, UV–visible, FT‐IR, mass spectra, and conductometric measurements. Advanced studies such as density functional theory (DFT) are employed to gain insights into the stable electronic configuration. Specifically, the study explores the proposed geometry, revealing a distorted octahedral structure for the complexes. The findings contribute as critical molecular characteristics of these newly synthesized complexes, paving the way for potential applications in diverse fields, including medicinal chemistry. Through an investigation into the antimicrobial properties, the efficacy of the synthesized compounds was assessed against a diverse range of bacterial and fungal strains. Remarkably, the complexes demonstrated significant antimicrobial activities, showing potential applications in combating various microbial infections. In an extended exploration of their medical utility, the compounds were examined for their antibiotic properties against Helicobacter pylori. The Schiff base and its metal complexes emerged as promising antibiotics with notable efficacy against H. pylori, suggesting their potential in addressing infections associated with this bacterium. Furthermore, the antitumor potential of the synthesized complexes was investigated, focusing on their impact on MCF‐7 (Breast carcinoma) cells. The organotin (IV) Schiff base complexes in this research showed remarkable efficacy, evidenced by their notably low IC50 values (9, 10, 11 μg/mL) in comparison with cisplatin. In addition to their potent antitumor effects, these complexes exhibited reduced cytotoxicity toward normal cells (VERO cells) compared with cisplatin. The investigation extends to molecular docking, where this approach aims to elucidate their interactions with specific protein structures, including (2JFZ, 1SC7, and 6W41). The primary objective is to clarify the potential properties of these compounds, focusing on their antibiotic efficacy, anti‐H. pylori activity, antitumor potential, and anti‐COVID‐19 properties. [ABSTRACT FROM AUTHOR]

Transformation of carbon dioxide and nitrate ions into urea offers an attractive route for both nitrogen fertilizer production and environmental remediation. However, achieving this transformation under mild conditions remains challenging. Herein, we report an efficient photoelectrochemical method for urea synthesis by co‐reduction of carbon dioxide and nitrate ion over a Cu2O photocathode, delivering urea formation rate of 29.71±2.20 μmol g−1 h−1 and Faradaic efficiency (FE) of 12.90±1.15 % at low external potential (−0.017 V vs. reversible hydrogen electrode). Experimental data combined with theoretical calculations suggest that the adsorbed CO* and NO2* species are the key intermediates, and associated C−N coupling is the rate‐determining step. This work demonstrates that Cu2O is an efficient catalyst to drive co‐reduction of CO2 and NO3− to urea under light irradiation with low external potential, showing great opportunity of photoelectrocatalysis as a sustainable tool for value‐added chemical synthesis. [ABSTRACT FROM AUTHOR]

Nucleoside and nucleotide analogues have proven to be transformative in the treatment of viral infections and cancer. One branch of structural modification to deliver new nucleoside analogue classes explores replacement of canonical ribose oxygen with a sulfur atom. Whilst biological activity of such analogues has been shown in some cases, widespread exploration of this compound class is hitherto hampered by the lack of a straightforward and universal nucleobase diversification strategy. Herein, we present a synergistic platform enabling both biocatalytic nucleobase diversification from 4′‐thiouridine in a one‐pot process, and chemical functionalization to access new entities. This methodology delivers entry across pyrimidine and purine 4′‐thionucleosides, paving a way for wider synthetic and biological exploration. We exemplify our approach by enzymatic synthesis of 5‐iodo‐4′‐thiouridine on multi‐milligram scale and from here switch to complete chemical synthesis of a novel nucleoside analogue probe, 5‐ethynyl‐4′‐thiouridine. Finally, we demonstrate the utility of this probe to monitor RNA synthesis in proliferating HeLa cells, validating its capability as a new metabolic RNA labelling tool. [ABSTRACT FROM AUTHOR]

Microflow catalysis is a cutting-edge approach to advancing chemical synthesis and manufacturing, but the challenge lies in developing efficient and stable multiphase catalysts. Here we showcase incorporating amine-containing metal-organic cages into automated microfluidic reactors through covalent bonds, enabling highly continuous flow catalysis. Two Fe4L4 tetrahedral cages bearing four uncoordinated amines were designed and synthesized. Post-synthetic modifications of the amine groups with 3-isocyanatopropyltriethoxysilane, introducing silane chains immobilized on the inner walls of the microfluidic reactor. The immobilized cages prove highly efficient for the reaction of anthranilamide with aldehydes, showing superior reactivity and recyclability relative to free cages. This superiority arises from the large cavity, facilitating substrate accommodation and conversion, a high mass transfer rate and stable covalent bonds between cage and microreactor. This study exemplifies the synergy of cages with microreactor technology, highlighting the benefits of heterogenous cages and the potential for future automated synthesis processes Microflow catalysis represents a cutting-edge method for advancing chemical synthesis and manufacturing, though developing efficient and stable multiphase catalysts remains challenging. Here the authors demonstrate the incorporation of amine-containing metal-organic cages into automated microfluidic reactors through covalent bonds, facilitating highly continuous flow catalysis. [ABSTRACT FROM AUTHOR]

A novel series of ligustrazine derivatives was designed, synthesized, and evaluated as acetylcholinesterase (AChE) and butylcholinesterase (BuChE) inhibitors for the treatment of Alzheimer's disease (AD). In vitro studies displayed that some of the synthesized compounds revealed promising AChE and BuChE inhibitory effects. Particularly, compounds E12 and E27, indicated highly AChE inhibitory activity with IC50 values of 1.85 μM and 0.98 μM, respectively and showed noteworthy protective effects against on glutamate-induced SH-SY5Y cells damage at 1 μM and 10 μM concentrations. Furthermore, molecular simulation docking elucidates compounds E12 and E27 interacting with residues in the binding site of AChE (PDB code: 4EY7) and BuChE (PDB code: 1P0I), emphasizing the protein residues that participate in the main interactions with the two targets. Taken together, these results revealed that compounds E12 and E27 might be potential lead compounds for further structure optimization in the drug-discovery process against AD. [ABSTRACT FROM AUTHOR]

Mixed ligand complexes of manganese(II), cobalt(II), copper(II), and cadmium(II)with an innovative Schiff base ligand denoted as (L1), 4-(2-((1E,2E)-1-(2-(p-tolyl)hydrazineylidene)propan-2-ylidene)hydrazineyl), served as the principal ligand, while glycine (L2) was employed as secondary ligand were successfully effectively characterized through a comprehensive set of analyses, including Elemental analysis, UV–Visible, FT-IR, Mass spectra, and conductometric measurements. Density functional theory (DFT) computations were executed to discern the enduring electronic arrangement, the energy gap, dipole moment and chemical hardness of the hybrid ligand assemblies. The proposed geometry for the complexes is a distorted octahedral structure. The antimicrobial efficacy of these compounds was assessed against a range of bacterial and fungal strains. Notably, these complexes exhibited promising antimicrobial activities, with the cadmium (II) complex demonstrating superior efficacy towards all tested organisms. These compounds were also examined for their antibiotic properties against H. pylori to explore their broader medical potential. The Schiff base ligand and its corresponding metal complexes displayed substantial potential as an antibiotic against H. pylori. Additionally, the antitumor potential of the synthesized complexes was assessed against MCF-7 (Breast carcinoma) cells—the Cu (II) complex demonstrated superior activity with the lowest IC50 value compared to cisplatin. Moreover, it exhibited reduced cytotoxicity towards normal cells (VERO cells) compared to cisplatin, establishing it as the most potent compound in the study. Furthermore, molecular docking was explored of the Schiff base ligand and its corresponding cadmium(II) complex. The analysis of the docking study yielded valuable structural insights that can be effectively utilized in conducting inhibition studies for example against COVID-19. This comprehensive study highlights these synthesized compounds' multifaceted applications and promising bioactive properties. [ABSTRACT FROM AUTHOR]

We present a methodology for the synthesis of inorganic-organic Janus-type molecules based on mono-T8 and difunctionalized double-decker silsesquioxanes (DDSQs) via hydrosilylation reactions, achieving exceptionally high yields and selectivities. The synthesized compounds were extensively characterized using various spectroscopic techniques, and their sizes and spatial arrangements were predicted through molecular modelling and density functional theory (DFT) calculations. Quantum chemical calculations were employed to examine the interactions among four molecules of the synthesized compounds. These computational results allowed us to determine the propensity for molecular aggregation, identify the functional groups involved in these interactions, and understand the changes in interatomic distances during aggregation. Understanding the aggregation behaviour of silsesquioxane molecules is crucial for tailoring their properties for specific applications, such as nanocomposites, surface coatings, drug delivery systems, and catalysts. Through a combination of experimental and computational approaches, this study provides valuable insights into the design and optimization of silsesquioxane-based Janus-type molecules for enhanced performance across various fields. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting is a promising technique for the production of high‐purity hydrogen. Substituting the slow anodic oxygen evolution reaction with an oxidation reaction that is thermodynamically more favorable enables the energy‐efficient production of hydrogen. Moreover, this approach facilitates the degradation of environmental pollutants and synthesis of value‐added chemicals through the rational selection of small molecules as substrates. Strategies for small‐molecule selection and electrocatalyst design are critical to electrocatalytic performance, with a focus on achieving a high current density, selectivity, Faradaic efficiency, and operational durability. This perspective discusses the key factors required for further advancement, including technoeconomic analysis, new reactor system design, meeting the requirements of industrial applications, bridging the gap between fundamental research and practical applications, and product detection and separation. This perspective aims to advance the development of hybrid water electrolysis applications. [ABSTRACT FROM AUTHOR]

A new series of substituted benzo[h]chromene, benzochromenopyrimidine, and benzochromenotriazolopyrimidine derivatives were synthesized via chemical transformations of iminonitrile, ethoxymethylene amino, and cyanomethylene functionalities. The chemical structures of the synthesized compounds were assured by spectroscopic data and elemental analysis. The larvicidal efficacy of these compounds against Culex pipiens L. larvae was investigated, revealing potent insecticidal activity, particularly for compounds 6, 10, and 16, exceeding that of the standard insecticide chlorpyrifos. The mode of action of these compounds was explored through molecular docking studies, indicating their potential as acetylcholine esterase (AChE) inhibitors and nicotinic acetylcholine receptors (nAChR) blockers. The structure–activity relationship analysis highlighted the influence of substituents and fused heterocyclic rings on larvicidal potency. These findings suggest that the synthesized compounds hold promise as potential candidates for developing novel and effective mosquito control agents. [ABSTRACT FROM AUTHOR]

Anti-microbial resistance has emerged as the leading cause of death worldwide with the rise of multidrug-resistant (MDR) bacteria, the need for novel anti-microbials to treat serious illnesses has become a great necessity. Hence, in this study, we aimed to design and synthesize benzothiazole-coupled azetidinone derivatives (GD1–GD12) as novel antibacterial agents. The synthesized compounds were elucidated by nuclear magnetic resonance, infrared and mass spectroscopy. The antibacterial activities of these compounds were tested against antibiotic-susceptible and MDR strains of bacteria. In addition, we performed ADME profiling, molecular docking and molecular dynamic simulations, principle component analysis, dynamic cross-correlation map and free-energy landscape to assess the binding of synthesized compounds with the β-lactamase. Among the synthesized compounds GD6 and GD5 displayed minimum inhibitory concentrations of 12.5 μg/mL and 50 μg/mL against MDR strains of E. coli; more effective than standard. The molecular docking of designed molecules was performed against β-lactamase enzyme and the stability of the complex was validated. The pharmacokinetic profile displayed the compounds to possess druggable properties within the suitable ranges. The in silico approach displayed compound GD6 to be stable with β-lactamase enzyme; indicating the mechanism for these compounds to be via inhibition of β-lactamase. The novel anti-microbial compounds assessed against susceptible and MDR strains of bacteria possess antibacterial potential via the inhibition of β-lactamase. The aforementioned data will be crucial to the development of novel broad-spectrum antibacterial compounds. [ABSTRACT FROM AUTHOR]

Efficiently exploring organic molecules through multi-step processes demands a transition from conventional laboratory synthesis to automated systems. Existing platforms for machine-assistant synthetic workflows compatible with multiple liquid-phases require substantial engineering investments for setup, thereby hindering quick customization and throughput increasement. Here we present a droplet-based chip that facilitates the self-organization of various liquid phases into stacked layers for conducting chemical transformations. The chip's precision polymer printing capability, enabled by digital micromirror device (DMD)-maskless photolithography and dual post-chemical modifications, allows it to create customized, sub-10 µm featured patterns to confine diverse liquids, regardless of density, within each droplet. The robustness and open design of surface-templated liquid layers actualize machine-assistant droplet manipulation, synchronous reaction triggering, local oscillation, and real-time monitoring of individual layers into a reality. We propose that, with further integration of machine operation line and self-learning, this droplet-based platform holds the potential to become a valuable addition to the toolkit of chemistry process, operating autonomously and with high-throughput. Existing platforms for machine assistant synthetic workflows compatible with multiple liquid phases lack the possibility of easy customization and throughput increasement. Here, the authors report a droplet-based chip that allows self-organization of various liquid phases into stacked layers for conducting chemical transformations. [ABSTRACT FROM AUTHOR]

Gold catalysis has emerged as a groundbreaking field in synthetic chemistry, revolutionizing numerous organic transformations. Despite the significant achieved advancements, the mechanistic understanding behind many gold‐catalyzed reactions remains elusive. This Concept article covers the so‐called "self‐activating" Au(I) complexes, sorting out their pivotal role in gold catalysis. We comment on how Au(I) complexes can undergo self‐activation, triggering diverse catalytic transformations without the need for external additives. The most important examples reported so far that underlie the catalytic activity of these species are discussed. This intrinsic reactivity represents a paradigm shift in gold catalysis, offering new avenues for the design of efficient and sustainable catalytic systems. Furthermore, we explore the factors influencing the stability, reactivity, and selectivity of these Au(I) complexes, providing insights into their synthetic utility and potential applications. This area of research not only advances our fundamental understanding of gold catalysis but also paves the way for the development of novel catalytic strategies with broad implications in organic synthesis and the chemical industry. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed [3+2] annulation reaction of exocyclic enamines/enol ethers with 1,4‐benzoquinone esters has been developed, providing facile access to N,O‐spiroketals and spiroketals under mild conditions with broad substrate scope (26 examples, 71–94 % yields). Gram scale synthesis and chemical transformations demonstrated that this method is potentially useful in the synthesis of natural products and drugs containing a N,O‐ spiroketal moiety. The chiral N,O‐spiroketal could be obtained with 98 % ee after recrystallization, when a chiral SaBOX ligand was employed. [ABSTRACT FROM AUTHOR]

Background: Xanthenes and multi-aryl carbon core containing compounds represent different types of complex and condensed architectures that have impressive wide range of pharmacological, industrial and synthetic applications. Moreover, indoles as building blocks were only found in naturally occurring metabolites with di-aryl carbon cores and in chemically synthesized tri-aryl carbon core containing compounds. Up to date, rare xanthenes with indole bearing multicaryl carbon core have been reported in natural or synthetic products. The underlying mechanism of fluorescein-like arthrocolins with tetra-arylmethyl core were synthesized in an engineered Escherichia coli fed with toluquinol remained unclear. Results: In this study, the Keio collection of single gene knockout strains of 3901 mutants of E. coli BW25113, together with 14 distinct E. coli strains, was applied to explore the origins of endogenous building blocks and the biogenesis for arthrocolin assemblage. Deficiency in bacterial respiratory and aromatic compound degradation genes ubiX, cydB, sucA and ssuE inhibited the mutant growth fed with toluquinol. Metabolomics of the cultures of 3897 mutants revealed that only disruption of tnaA involving in transforming tryptophan to indole, resulted in absence of arthrocolins. Further media optimization, thermal cell killing and cell free analysis indicated that a non-enzyme reaction was involved in the arthrocolin biosynthesis in E. coli. Evaluation of redox potentials and free radicals suggested that an oxygen-mediated free radical reaction was responsible for arthrocolins formation in E. coli. Regulation of oxygen combined with distinct phenol derivatives as inducer, 31 arylmethyl core containing metabolites including 13 new and 8 biological active, were isolated and characterized. Among them, novel arthrocolins with p-hydroxylbenzene ring from tyrosine were achieved through large scale of aerobic fermentation and elucidated x-ray diffraction analysis. Moreover, most of the known compounds in this study were for the first time synthesized in a microbe instead of chemical synthesis. Through feeding the rat with toluquinol after colonizing the intestines of rat with E. coli, arthrocolins also appeared in the rat blood. Conclusion: Our findings provide a mechanistic insight into in vivo synthesis of complex and condensed arthrocolins induced by simple phenols and exploits a quinol based method to generate endogenous aromatic building blocks, as well as a methylidene unit, for the bacteria-facilitated synthesis of multiarylmethanes. [ABSTRACT FROM AUTHOR]

Solvents are essential for chemical synthesis and material preparation; however, traditional solvents face challenges in meeting safety and sustainability standards. Consequently, there is a growing focus on environmentally friendly solvent systems for polymeric materials, with deep eutectic solvents (DESs) standing out as promising alternatives owing to their eco-friendly attributes. In this review, we summarize studies on this novel solvent system in a broad range of applications, where DESs play multiple roles in polymer synthesis and corresponding material fabrication. In detail, we focus on the utilization of DESs in the synthesis of green polymers and related functional polymeric materials ranging from soft materials such as gels and nanofibers to membranes, films, and complex architectures generated from various techniques such as 3D printing, electrospinning, and self-assembly, together with their properties. Moreover, we discuss the green credentials through sustainability analysis and life-cycle assessment of DES-based polymeric materials. We believe this review will inspire more investigation into the use of DESs for functional green polymeric materials towards a sustainable future. [ABSTRACT FROM AUTHOR]

AbstractSix monoligated N-heterocyclic carbene-PdCl2-cyanopyridine complexes were prepared (N-heterocyclic carbene = NHC). X-ray single crystal diffraction analysis indicated that the complexes showed mononuclear Pd–NHC structures with two chlorides and the N-donor from cyanopyridine as ancillary ligands. The lengths of the Pd–C bonds in all complexes were 1.959(5)–1.976(3) Å, comparable to those found in the corresponding Pd–NHC catalysts. The catalytic activities of the well-defined Pd–NHC complexes have been evaluated with respect to the Hiyama cross-coupling reactions of aryl trialkoxysilanes with aryl chlorides. With 1.0 mol% Pd-catalyst, all synthesized palladium compounds have shown moderate to good catalytic activities for the coupling reactions. [ABSTRACT FROM AUTHOR]

Aromatic nitro compounds are important intermediates in synthetic organic chemistry. In this work, catechol was used as raw materials, and nitro‐catechol derivatives with different alkylation substitutions were synthesized using two different synthetic routes. More than 15 new previously undescribed compounds were obtained. Each compound was meticulously characterized using a suite of physicochemical techniques, with selective compounds further analyzed via X‐Ray diffraction to ascertain their structure. These newly synthesized compounds hold significant promise as candidates for further chemical modification, which underlines their potential usefulness in the field of the fine synthesis of organic compounds. [ABSTRACT FROM AUTHOR]

Nanoparticles exhibit distinct physical and chemical characteristics and are becoming increasingly significant in the production of innovative nanodevices for many applications in physics, biology, biomedicine, and pharmaceuticals. The aim of this research work is to synthesize Fe (II) and Cu (II) nano-sized complexes of trimethoprim (TMP) using the sonication method, characterize them using physical and spectroscopic methods, and carry out ADMET studies on the synthesized complexes. The spectroscopic and physical studies showed a change in colour and an increase in melting point due to coordination. The novel compounds were slightly soluble in water. The XRD tests revealed that the new nanocomplexes were crystalline. The Fe (II) nanocomplexes had a size of 57.56 nm and the Cu (II) nanocomplexes had a size of 69.88 nm. These values were found using Debye-Scherrer’s equation. The FTIR results of the TMP, Fe (II), and Cu (II) nanometal complexes showed a shift of the amino group band from 3317 to 3295 and 3202 cm−1 and the azomethine band from 1633 to 1625 and 1592 cm−1 in the complexes. In the complexes, the proton NMR spectra revealed an upfield shift of the amine proton. The carbon-13 NMR spectra showed that CH2 was involved in coordination with the metal ions. The spectra studies indicated that TMP coordinated with the metal ions through the methylene and amino groups. A trigonal bipyramid structure was proposed for the complexes. The results of the Rule of 5 studies indicated that the test compounds had a good drug-likeness prediction, with only one violation. The ADMET prediction showed that all of the compounds demonstrated improved pharmacokinetic characteristics and adhered to the RO5 requirement. These findings highlight the therapeutic potential of Fe (II) and Cu (II) nano-sized TMP complexes as bioactive compounds that warrant further investigation for pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Nanoparticle drug delivery systems are precisely designed technologies that utilize nanoparticles to deliver therapeutic drugs to specific targets and regulate their release. In recent times, nanoparticles have garnered significant interest owing to their potential for efficient drug delivery. This work is aimed at synthesizing Fe(II) and Cu(II) nano-sized complexes of sulfamethoxazole (SMX) using the sonication method. The physical and spectroscopic studies showed a colour change from white to grey, and a decrease in melting points suggested the formation of the metal complexes. The nanometal complexes were insoluble in water. XRD analysis showed that the crystallite sizes of Fe(II) and Cu(II) nanometal complexes were determined to be 76.08 nm and 37.13 nm, respectively, using the Debye-Scherrer equation. The FTIR results of the SMX, Fe(II), and Cu(II) nanometal complexes showed a shift of the amine band from 3243 to 3191 cm−1 and the sulfone band from 1154 to 1092 cm−1 in both complexes. The proton NMR showed a shift of the amine proton from 6.100 ppm to 6.035 ppm in the spectra of the Cu(II) complex. The amine chemical shift was absent in the spectra of the Fe(II) complex, showing deprotonation. The carbon-13 NMR spectra showed a similar chemical shift. The spectra studies indicated that SMX coordinated with the metal ions through the amino and sulfone groups. A tetrahedral structure was proposed for the complexes. SMX coordinated as a bidentate ligand to Fe(II) and Cu(II) ions. [ABSTRACT FROM AUTHOR]

Malaria is an intracellular protozoan parasitic disease caused by Plasmodium species with significant morbidity and mortality in endemic regions. The complex lifecycle of the parasite and the emergence of drug‐resistant Plasmodium falciparum have hampered the efficacy of current anti‐malarial agents. To circumvent this situation, the present study attempts to demonstrate the blood‐stage anti‐plasmodial action of 26 hybrid compounds containing the three privileged bioactive scaffolds (sulfonamide, chalcone, and nitro group) with synergistic and multitarget action. These three parent scaffolds exhibit divergent activities, such as antibacterial, anti‐malarial, anti‐fungal, anti‐inflammatory, and anticancer. All the synthesised compounds were characterised using various spectroscopic techniques. The in vitro blood‐stage inhibitory activity of 26 hybrid compounds was evaluated against mixed‐stage culture (asynchronize) of human malarial parasite P. falciparum, Pf 3D7 at different concentrations ranging from 25.0 µg/mL to 0.78 µg/mL using SYBR 1 green assay, with IC50 values determined after 48 h of treatment based on the drug‐response curves. Two potent compounds (11 and 10), with 2‐Br and 2,6‐diCl substitutions, showed pronounced activity with IC50 values of 5.4 µg/mL and 5.6 µg/mL, whereas others displayed varied activity with IC50 values ranging from 7.0 µg/mL to 22.0 µg/mL. Both 11 and 10 showed greater susceptibility towards mature‐stage trophozoites than ring‐stage parasites. The hemolytic and in vitro cytotoxicity assays revealed that compounds 11 and 10 did not cause any toxic effects on host red blood cells (uninfected), human‐derived Mo7e cells, and murine‐derived BA/F3 cells. The in vitro observations are consistent with the in silico studies using P. falciparum‐dihydrofolate reductase, where 11 and 10 showed a binding affinity of −10.4 Kcal/mol. This is the first report of the hybrid scaffold, 4‐nitrobenzenesulfonamide chalcones, demonstrating its potential as an anti‐plasmodial agent. [ABSTRACT FROM AUTHOR]