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ABSTRACT Reduction of carboxamides is an efficient approach to obtain the corresponding amines, albeit it is one of the most problematic. In this work, by use of pinacolborane (HBpin) as a reductant, the rare‐earth metal tris (arylamido) complex supported by a ferrocenyl‐modified arylamido ligand La[NH‐2,6‐iPr2‐4‐FcC6H2]3 was employed as a precatalyst for primary and secondary amide reductions. This catalyst system exhibited high activity toward hydroborative reduction of amides to amines under mild conditions, as well good tolerance for heteroatoms and functional groups in the reduction. A lanthanide hydride was experimentally verified as the active species and the reduction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Ammonia decomposition to H2 (ADH) is one of the key reactions in the ammonia‐based energy system. Recent research has been focused on developing more active and affordable catalysts, however, few can operate below 500 °C and typically require the expensive metal ruthenium. Herein, a fundamentally different thermal ADH via a chemical looping process (CLADH) mediated by alkali metal and its amide pairs, which can work under lower temperatures than the catalytic process, is reported. This CLADH consists of two steps: 1) Ammoniation step ̶ NH3 reacts with Na or K to generate NaNH2 or KNH2, respectively, accompanied by releasing one‐third of H2 in NH3 at room temperature; 2) Decomposition step ̶ NaNH2 or KNH2 decomposes to N2 and H2 with the regeneration of Na or K which can be performed above 275 °C. Additionally, due to the significant enthalpy change in the two‐step reactions of this CLADH, −78.0 kJ mol−1 for the first step and 123.9 kJ mol−1 for the second, using the Na and NaNH2 pair—suggest potential for thermal energy storage. This work not only reports an alternative route to produce H2 from NH3, but also unravels the potential of chemical looping process for thermal energy storage. [ABSTRACT FROM AUTHOR]

Cyano and amide are important functionalities in medicinal chemistry, and organic chemistry transformations. We have devised a new, safe, and easy method for the synthesis of cyano and further amide using aldehyde via copper-mediated cyanation and amidation with ammonium acetate/iodine in DMF in a time-dependent manner. This approach efficiently converts aryl/alkyl/hetero aldehydes into their corresponding cyano which can be isolated after 3 h and/or if continued for 24 h then in-situ transformed into amide derivatives. Herein cupric acetate plays the role of coordinator, ammonium acetate is the nitrogen source, while DMF serves as a carbon source. We did easy and safe cyanation to explore the synthesis of varieties of cyano in 69–86% yields and respective amide derivatives in 58–75% yields. Thus, this process can serve the dual advantage in the synthesis of cyano and amides bioactive scaffold using respective aldehyde. [ABSTRACT FROM AUTHOR]

The Sonogashira coupling reaction and hydration of nitriles were demonstrated using a facile catalytic system comprising a readily available cobalt salt and an environmentally friendly room-temperature ionic liquid, choline hydroxide (ChOH). The present system offers an alternative pathway for constructing Csp–Csp2 bonds through the alkynylation of aryl iodides in an aqueous environment, without the need for palladium- or copper-metal catalysts, phosphine ligands, or any external bases, albeit with some limited scope. Building upon the advantages and drawbacks of the present system employed in the Sonogashira coupling, we further extend its application to showcase the conversion of nitriles into amides, revealing the respective roles of ChOH and cobalt salt in the hydration of nitriles. The Sonogashira coupling and nitrile hydration were accomplished with cobalt salt and choline hydroxide (ChOH). Aryl iodides underwent alkynylation without external additives, albeit with limitations. Roles of ChOH and cobalt salt in nitrile hydration were also demonstrated. [ABSTRACT FROM AUTHOR]

As triboelectric nanogenerator (TENG) technology continue to evolve, its application in harsh environments has increasingly captivated the interest of researchers. However, the current research on heat-resistant triboelectric materials remains predominantly focused on the development of tribo-negative materials, with scant attention given to their equally crucial tribo-positive counterparts. In this study, the tribo-positive polyimide (PI) material with enhanced tribo-positivity is developed by integrating amide groups with electron-donating effects into the molecular chain. Furthermore, the TENG devices based on this series of tribo-positive PI materials have demonstrated an open-circuit voltage (VOC) of 242 V, a short-circuit current (ISC) of 8.13 μA, and a transferred charge (QSC) of 117 nC. Notably, these devices also demonstrate the capability to efficiently generate electricity even under elevated temperature conditions. This work not only proposes a potential molecular design strategy for developing high-performance tribo-positive PI materials applicable in TENGs, but also markedly propels the advancement of robust energy-harvesting devices engineered for operation at elevated temperatures. [ABSTRACT FROM AUTHOR]

Residues of the fungicides difenoconazole, propiconazole, cyflufenamid, and mandipropamid were determined in tomato fruit using acetonitrile for extraction and LC-MS/MS for quantification. Validation criteria include linearity range, the limit of detection (LOD) and limit of quantitation (LOQ), accuracy in terms of precision and trueness, and matrix effect were studied. The recovery rates of the method ranged from 91.8 to 106.3%. The precision of the method in terms of repeatability at one day (RSDr) and between three days (RSDR) ranged from 2.8 to 6.4% and from 4.3 to 7.6%, respectively, with good trueness from 92.2 to 96.4%. Matrix effects (suppression effects) ranged from 3.8% to 11.1%. The validated method was used to evaluate the dissipation kinetics of three different premix formulations: 30% EC (15% difenoconazole + 15% propiconazole), 14% DC (12.5% difenoconazole + 1.5% cyflufenamid), and 50% SC (25% difenoconazole + 25% mandipropamid) used on field tomatoes in Egypt. A first-order kinetic equation best describes residue dissipation. The calculated half-lives of difenoconazole, propiconazole, cyflufenamid, and mandipropamid were 2.01–2.27, 1.89, 1.97, and 1.71 days, respectively. The dissipation rate of difenoconazole did not differ significantly in the three premix formulations. Mandipropamid also dissipated faster compared to the other fungicides tested. The chronic dietary risk assessment results showed a minimal risk to adult Egyptian consumers. Waiting periods were advised for the safe consumption of tomatoes treated with the tested premix formulations. [ABSTRACT FROM AUTHOR]

Root canal irrigation endodontic solutions have effects on the chemistry of dentin. Infrared spectroscopy is a non-destructive chemical characterization method where the strength of absorption often correlates with mineral or organic composition. To survey effects of commonly used irrigation solutions on the composition of root dentin as detected by widely-available Fourier transform infrared spectroscopy (FTIR) methods. Electronic databases were searched for articles published between 1983 to 2023. After risk of bias assessments (OHAT), studies were grouped according to effects per irrigation solution. Inclusion criteria comprised in vitro studies that used extracted human or bovine teeth, treated by irrigation solutions characterized using FTIR spectroscopy and presenting spectral data. Publications that did not present spectra were excluded. A wide range of concentrations, durations, and treatment protocols have been tested but only 30 out of 3452 studies met our inclusion criteria. Different FTIR methods were used with Attenuated Total Reflection (ATR) variant being the most common (21 studies). Investigated solutions included sodium hypochlorite (NaOCl), ethylenediaminetetraacetic-acid (EDTA), 1-hydroxyethylidene-1–1-diphosphonic-acid (HEDP), peracetic-acid (PAA), glycolic-acid (GA), and citric-acid (CA) though most focused on NaOCl and EDTA. All solutions had detectable effects in the FTIR signature of dentin. NaOCl mainly affects the organics, revealing reduced amide/phosphate ratios with increasing concentrations. EDTA mainly effects the inorganic component, with the effects increasing with time and concentration, yet glycolic acid has stronger effects than EDTA on dentin. Beyond the type of irrigant and dentin exposure durations, concentration and protocol of application had strong effects. There is a lack of studies comparing similar irrigants under conditions that mimic clinical scenarios analyzing bulk sample because FTIR of powder dentin differs from FTIR of bulk dentin. The ideal root-canal irrigant should combine local disinfection properties with minimal compositional effects on healthy dentin. FTIR methods appear reliable to identify important changes in root dentin chemical composition. Such information can help understand when endodontic irrigation might lead to root degradation or possibly contribute to long term failures such as vertical fractures. Awareness of chemical damage from irrigation procedures may help clinicians select procedures that reduce deleterious effects on the root canal structures. [Display omitted] [ABSTRACT FROM AUTHOR]

As triboelectric nanogenerator (TENG) technology continue to evolve, its application in harsh environments has increasingly captivated the interest of researchers. However, the current research on heat-resistant triboelectric materials remains predominantly focused on the development of tribo-negative materials, with scant attention given to their equally crucial tribo-positive counterparts. In this study, the tribo-positive polyimide (PI) material with enhanced tribo-positivity is developed by integrating amide groups with electron-donating effects into the molecular chain. Furthermore, the TENG devices based on this series of tribo-positive PI materials have demonstrated an open-circuit voltage (VOC) of 242 V, a short-circuit current (ISC) of 8.13 μA, and a transferred charge (QSC) of 117 nC. Notably, these devices also demonstrate the capability to efficiently generate electricity even under elevated temperature conditions. This work not only proposes a potential molecular design strategy for developing high-performance tribo-positive PI materials applicable in TENGs, but also markedly propels the advancement of robust energy-harvesting devices engineered for operation at elevated temperatures.

Peptide−oligonucleotide conjugates (POCs) are covalent architectures composed of a DNA or RNA molecules linked to a peptide. These constructs have found widespread applications ranging from hybrid nanomaterials to gene‐targeted therapies. Considering the important role of POCs, a new catalytic approach for their preparation is reported here, that could be applied either on solid support in anhydrous media, or post‐synthetically in aqueous buffer. Single amino acids, peptides and cell penetrating peptides (CPPs) were conjugated to various oligo(ribo)nucleotides with high conversions and good isolated yields. The applicability of the method was demonstrated on more than 35 examples including an analogue of a commercial therapeutic oligonucleotide. Other conjugation partners, such as deoxycholic acid and biotin were also successfully conjugated to oligonucleotides. To highlight the potential of this catalytic approach, these conditions have been applied to iterative processes, which is of high interest for the development of DNA‐Encoded Libraries. [ABSTRACT FROM AUTHOR]

Herein, an environmentally friendly and efficient amidation method of imines by Oxone and CuO has been developed. This facile method shows excellent selectivity without affecting other functional groups such as phenyls, halogens, cyans, esters or heterocycles. This method features a broad substrate scope, mild conditions and high yields (≤90 %), and the yield in the gram scale experiment also reaches up to 81 %. Flonicamid, moclobemide and bupivacaine are also successfully synthesized to demonstrate its potential utilities. [ABSTRACT FROM AUTHOR]

BACKGROUND: Faced with the need to develop new herbicides with modes of action different to those observed for existing agrochemicals, one of the most promising strategies employed by synthetic chemists involves the structural modification of molecules found in natural products. Molecules containing amides, imides, and epoxides as functional groups are prevalent in nature and find extensive application in synthesizing more intricate compounds due to their biological properties. In this context, this paper delineates the synthesis of N‐phenylnorbornenesuccinimide derivatives, conducts biological assays, and carries out in silico investigation of the protein target associated with the most potent compound in plant organisms. The phytotoxic effects of the synthesized compounds (2–29) were evaluated on Allium cepa, Bidens pilosa, Cucumis sativus, Sorghum bicolor, and Solanum lycopersicum. RESULTS: Reaction of endo‐bicyclo[2.2.1]hept‐5‐ene‐3a,7a‐dicarboxylic anhydride (1) with aromatic amines led to the N‐phenylnorbornenesuccinic acids (2–11) with yields ranging from 75% to 90%. Cyclization of compounds (2–11) in the presence of acetic anhydride and sodium acetate afforded N‐phenylnorbornenesuccinimides (12–20) with yields varying from 65% to 89%. Those imides were then subjected to epoxidation reaction to afford N‐phenylepoxynorbornanesuccimides (21–29) with yields from 60% to 90%. All compounds inhibited the growth of seedlings of the plants evaluated. Substance 23 was the most active against the plants tested, inhibiting 100% the growth of all species in all concentrations. Cyclophilin was found to be the enzymatic target of compound 23. CONCLUSION: These findings suggest that derivatives of N‐phenylnorbornenesuccinimide are promising compounds in the quest for more selective and stable agrochemicals. This perspective reinforces the significance of these derivatives as potential innovative herbicides and emphasizes the importance of further exploring their biological activity on weeds. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Typified by LiTMP and TMPMgCl.LiCl, (TMP=2,2,6,6‐tetramethylpiperidide), s‐block metal amides have found widespread applications in arene deprotonative metalation. On the contrary, transition metal amides lack sufficient basicity to activate these substrates. Breaking new ground in this field, here we present the synthesis and full characterisation of earth‐abundant transition metals M(TMP)2 (M=Fe, Co). Uncovering a new reactivity profile towards fluoroarenes, these amide complexes can promote direct M−H exchange processes regioselectively using one or two of their basic amide arms. Remarkably, even when using a perfluorinated substrate, selective C‐H metalation occurs leaving C−F bonds intact. Their kinetic basicity can be boosted by LiCl or NBu4Cl additives which enables formation of kinetically activated ate species. Combining spectroscopic and structural studies with DFT calculations, mechanistic insights have been gained on how these low polarity metalation processes take place. M(TMP)2 can also be used to access ferrocene and cobaltocene by direct deprotonation of cyclopentadiene and undergo efficient CO2 insertion of both amide groups under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Amino acids are one of the most important building blocks of life. During the biochemical process of translation, cells sequentially connect amino acids via amide bonds to synthesize proteins, using the genetic information in messenger RNA (mRNA) as a template. From a prebiotic perspective (i.e., without enzymatic catalysis), joining amino acids to peptides via amide bonds is difficult due to the highly endergonic nature of the condensation reaction. We show here that amides can be formed in reactions catalyzed by the transition metal sulfides from acetylene, carbon monoxide and ammonia under aqueous conditions. Some α- and β-amino acids were also formed under the same conditions, demonstrating an alternative cyanide-free path for the formation of amino acids in prebiotic environments. Experiments performed with stable isotope labeled precursors, like 15NH4Cl and 13C-acetylene, enabled the accurate mass spectroscopic identification of the products formed from the starting materials and their composition. Reactions catalyzed using the transition metal sulfides seem to offer a promising alternative pathway for the formation of amides and amino acids in prebiotic environments, bypassing the challenges posed by the highly endergonic condensation reaction. These findings shed light on the potential mechanisms by which the building blocks of life could have originated on early Earth. [ABSTRACT FROM AUTHOR]

In this study, [(N-benzamidomethyl)(N-benzoyl)amino]methyltriphenylphosphonium tetrafluoroborate was synthesized at 80 °C, starting from N-benzoylaminomethyltriphenylphosphonium tetrafluoroborate, by a specific α-amidoalkylation reaction using Hünig's base as a catalyst. N-benzoylaminomethyltriphenylphosphonium tetrafluoroborate acts as both an amidoalkylating agent and a nucleophile precursor. The structure of the compound obtained was confirmed by spectroscopic methods (1H-, 13C-, 31P-NMR, IR) and HR-MS analysis. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of (±)-2-chloro-N-(4-methyl-2-oxo-2H-chromen-7-yl)-2-phenylacetamide through the reaction of 7-amino-4-methyl-2H-chromen-2-one with (±)-2-chloro-2-phenylacetyl chloride. The in vitro anti-inflammatory activity of the new compound was evaluated, and the results indicated that it exhibited superior activity compared to the standard, ibuprofen. The bio-functional hybrid compound underwent thorough detailed characterization utilizing 1H and 13C NMR, UV, and mass spectral analysis. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of N-(3-chlorophenethyl)-4-nitrobenzamide in the reaction between 2-(3-chlorophenyl)ethan-1-amine and 4-nitrobenzoyl chloride. The newly obtained bio-functional hybrid molecule was fully characterized via 1H, 13C NMR, UV, and mass spectral data. [ABSTRACT FROM AUTHOR]

The continuous search for more effective options against well-known pathogens such as Candida albicans remains the rationale for the search for novel lead compounds from various sources. This study aims to investigate the chemical structure, chemical properties, of 5-(2-((5-(((1S,3R) -3-(5-acetamido-1,3,4-thiadiazolidin-2-yl) cyclopentyl) methyl)-1,3,4-thiadiazolidin-2-yl)amino)-2-oxoethyl)-2-methyl-2,3-dihydro-1H-pyrazol-3-ide designated ATCTP using DFT method ωB97XD/-311 + + g(2d, 2p) and the biological potential of compound ATCTP against Candida albicans using molecular docking and ADMET studies. Geometry optimization was carried out in DMSO, ethanol. gas and water revealing minute discrepancies in bond length and wider differences in bond angles. Frontier molecular orbital investigations reveal HOMO–LUMO energy gap magnitude in decreasing order of ATCTP_Gas > ATCTP_Water > ATCTP_ethanol > ATCTP_DMSO inferring that water influences chemical stability of the compound the most compared to ethanol and DMSO. Density of state investigations have revealed electron density contributions at corresponding energy peaks. In silico pharmacokinetic predicts ATCTP not to be cytotoxic, hepatotoxic, immunotoxic or mutagenic but probable mutagen. Molecular docking investigation of ATCTP against aspartic proteinase of Candida albicans (ID: 2QZX) in comparison with standard drug Fluconazole. Compound ATCTP had higher binding affinity (− 8.1 kcal/mol) compared to that of the standard drug fluconazole (− 5.6 kcal/mol) which records 4 conventional hydrogen interactions compared to 2 formed in the interaction of ATCTP + 2QZX. ATCTP also reports binding affinity of − 7.2 kcal/mol which reportedly surpassed that of 2QZX interaction with fluconazole (− 5.7 kcal/mol). ATCTP binds with lanosterol14-α-demethylase (5v5z) with binding affinity of − 9.7 kcal/mol binding to active site amino acid residues of the protein compared to fluconazole + 5v5z (− 8.0 kcal/mol). ATCTP is therefore recommended to be a lead compound for the possible design of a new and more effective anti-candida therapeutic compound. [ABSTRACT FROM AUTHOR]

Acyl fluorides have emerged as versatile reagents in various synthetic endeavors, offering a range of advantages over their counterparts, acyl chlorides. This study delves into the properties and reactivity of acyl fluorides, particularly their reaction with amines and alcohols, to elucidate their distinct characteristics. We also introduce a facile and practical synthesis of acyl fluorides from a stable solution of CF3O− salt. Additionally, we establish an efficient one‐pot process for the direct preparation of amides or esters from corresponding acids and amines or alcohols, showcasing the remarkable efficiency of acyl fluorides in these transformations. [ABSTRACT FROM AUTHOR]

Klassische Schutzgruppenchemie erfordert unweigerlich einen Entschützungsschritt, um die ursprünglich blockierte Funktionalität vor weiteren Umwandlungen wiederherzustellen. Da dieser Aspekt der Schutzgruppenmanipulation zwangsläufig die Anzahl der Schritte jeder Synthesesequenz erhöht, bieten Methoden, die eine gleichzeitige Entschützung und Funktionalisierung ermöglichen („entschützende Funktionalisierung", im Gegensatz zur Entschützung mit anschließender Funktionalisierung), attraktive Vorteile, um die Effizienz zu steigern und synthetische Routen zu verkürzen. In diesem Bericht präsentieren wir eine Methode zur entschützenden Funktionalisierung der neu eingeführten Nms‐Amide, die auf einer Analyse mittels Dichtefunktionaltheorie (DFT) basiert und die inhärente Nms‐Reaktivität ausnutzt. Mechanistische Studien erklären außerdem warum andere häufig verwendete Schutzgruppen nicht die gleichen Reaktivitätsmuster aufweisen. Die Anwendbarkeit dieses Ansatzes wurde anhand zahlreicher Substrate demonstriert und schließlich verwendet, um Arzneimittelderivate effizienter und mit verkürzten Synthesewegen herzustellen. [ABSTRACT FROM AUTHOR]

N,O‐acetals are found as structural motifs in natural products and are important synthetic precursors for N‐acylimines as building blocks in organic synthesis for C−C‐bond formation and amines. For the synthesis of N,O‐acetals, an acid‐, base‐ and metal‐free catalytic method is reported applying N,N‐di‐(2,6‐diisopropyl)‐1,7‐dicyano‐perylen‐3,4,9,10‐tetracarboxylic acid imide and N,N‐di‐(2,6‐diisopropyl)‐1,6,7,12‐tetrabromo‐2,5,8,11‐tetracyano‐perylen‐3,4,9,10‐tetracarboxylic acid imide as extremely electron‐deficient photocatalysts. The first perylene bisimide highly selectively photocatalyzes the formation of the N,O‐acetals as products in high yields, and the second and more electron‐deficient perylene bisimide allows these reactions without thiophenol as an H‐atom transfer reagent. Calculated electron density maps support this. The reaction scope comprises different substituents at the nitrogen of the enamides and different alcohols as starting material. Dehydroalanines are converted to non‐natural amino acids which shows the usefulness of this method for organic and medicinal chemistry. [ABSTRACT FROM AUTHOR]

This research is based on the synthesis, characterization and in vitro α‐glucosidase inhibitory activity of fourteen amides (2 a–2 n) of flurbiprofen drug. Seven compounds in the series displayed potent inhibitory activity having IC50 values (IC50=5.67±0.89 μM) to (IC50=17.87±2.39 μM) in comparison with acarbose standard (IC50=875.75±1.24 μM). The FMO of 2 a–2 n molecules was quantified by the DFT assay. The promising value for energygap explained the higher poteny agannist α‐glucosidase. MEP provides the insights into the distribution of electrostatic potential on the molecular surface of 2 a–2 n, showing that C=O group has the highest negative potential. The AIM investigation revealed minimal hydrogen bond energy and non‐covalent interactions. This suggests that these molecules may have limited hydrogen bonding and non‐covalent interactions, which could be relevant to their chemical behavior. Molecular docking and (MEP) showed the C=O group, with its high negative potential, is a key in recognizing the catalytic non‐polar regions of enzymes, such as TYR72, GLU277, and ARG442. Similarly, the hydrophobic regions of investigated compounds play a significant role in identifying essential amino acids like ASP352 and ARG442, which are vital for the ligand's proper orientation and subsequent biological activity. [ABSTRACT FROM AUTHOR]

Amidation synthesis stands as a significant area in organic chemistry. Incorporating cutting-edge amidation methods into basic organic chemistry laboratory teaching can enhance educational content and foster integration between undergraduate teaching and research achievements. Herein, we report an experiment focusing on the umpolung of aldehydes catalyzed by N-heterocyclic carbene (NHC) for amide synthesis. Utilizing benzaldehyde and nitrosobenzene as substrates, N-hydroxy-N-phenylbenzoylamide was efficiently synthesized under anhydrous and oxygen-free conditions. The reaction progress was monitored via thin-layer chromatography (TLC), and the product structure was confirmed by infrared and nuclear magnetic resonance spectroscopy. This experiment offers simplicity in operation, mild reaction conditions, high atom economy, and excellent repeatability, rendering it highly suitable for undergraduate laboratory teaching. By amalgamating the pivotal concept of umpolung with the cuttingedge science of N-heterocyclic carbene catalysis, this experiment aims to stimulate and nurture students' interest in scientific inquiry. [ABSTRACT FROM AUTHOR]

The total synthesis of lobatamides A (1 a) and C (1 c) via a common bislactone intermediate is reported. The allylic aryl moiety including a trisubstituted Z‐olefin was constructed by hydroboration of a 1,1‐disubstituted allene and subsequent Migita‐Kosugi‐Stille coupling. Although the seco acid proved to be highly unstable even in the presence of weak bases, Zhao macrolactonization under acidic conditions via the α‐acyloxyenamide successfully provided the common bislactone intermediate. Hydrozirconation‐iodination of the terminal alkyne and subsequent copper‐mediated coupling with primary amides proceeded successfully in the presence of the sensitive bislactone framework. The developed synthetic route enables the late‐stage installation of enamide side chains, which are crucial structures for V‐ATPase inhibition. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel nickel‐catalyzed practical and simple synthesis of thioesters from amides and disulfides has been developed. Diverse substituted aromatic amides are capable of coupling with diaryl or dialkyl disulfides via C−N/S−S bonds cleavage to produce the desirable thioesters in moderate to good yields. This procedure features cheap metals, novel and easily preparative substrates, providing a simple and practical access to a variety of thioesters without toxic thiols or CO gas. [ABSTRACT FROM AUTHOR]

Herein we report an atom‐economical, transition metal‐free method for synthesizing 2‐aryl quinazolinones through a cascade annulation of 2‐amino benzamide and benzyl alcohol. The reaction proceeds via KOtBu‐mediated acceptorless alcohol dehydrogenation pathways. The procedure tolerates a wide variety of functional groups and provides a convenient method for the synthesis of 2‐aryl quinazolinones. Mechanistic insights by experiments and DFT calculations lead to unveil the reaction mechanism. [ABSTRACT FROM AUTHOR]

Recently, hydrogen‐bonded organic frameworks (HOFs) have emerged as a rapidly advancing class of porous materials with significant potential for applications in the absorption and detection of various chemicals. Here, the unique ability of amide groups to form endless‐stacking H‐bonds is implemented in the design of HOFs. Starting from benzene‐1,3,5‐tricarboxamide and amide‐containing tribenzocyclynes as foundational building blocks, a diverse range of HOFs featuring 1D, 2D, or 3D hydrogen‐bonded frameworks has been synthesized. Among those, all three porous HOFs, HOF_B‐Hex, HOF_T‐Pr and HOF_T‐Hex exhibited permanent porosity, thereby demonstrating the effectiveness of amide‐based HOFs strategy. Notably, HOF_T‐Hex stands out with a 42% pore volume and an impressive iodine capture efficiency of 6.4 g g−1. The iodine capture capacity is influenced not only by pore volume but also by the presence of accessible π‐electrons within the material (i.e., electrons not engaged in a π–π stacking interaction. Furthermore, some of these HOFs exhibited fluorescent responses to iodine positioning them as highly promising materials for both the capture and sensing of iodine. [ABSTRACT FROM AUTHOR]

In this study, we synthesized two coordination complexes based on pyrazole-based ligands, namely 1,5-dimethyl-N-phenyl-1H-pyrazole-3-carboxamide (L1) and 1,5-dimethyl-N-propyl-1H-pyrazole-3-carboxamide (L2), with the aim to investigate bio-inorganic properties. Their crystal structures revealed a mononuclear complex [Ni(L1)2](ClO4)2 (C1) and a dinuclear complex [Cd2(L2)2]Cl4 (C2). Very competitive antifungal and anti-Fusarium activities were found compared to the reference standard cycloheximide. Additionally, L1 and L2 present very weak genotoxicity in contrast to the observed increase in genotoxicity for the coordination complexes C1 and C2. [ABSTRACT FROM AUTHOR]

A total of eighteen novel 2-(1H-indol-1-yl)-N-(5-phenyl-1,3,4-thiadiazol-2-yl) acetamide derivatives were synthesized through the condensation reaction of 2-(1H-indol-1-yl) acetic acid and 5-phenyl1,3,4-thiadiazol-2-amine via fragment-based design strategy. The target compounds were subjected to screening for antibacterial activity against Xanthomonas oryzae pv. Oryzae, Xanthomonas axonopodis pv. Citri and Pseudomonas syringae pv. Actinidiae. The preliminary antibacterial evaluation of the target compounds showed that some target compounds possessed moderate to good activities against Xoo and Xac. Among them, compound 3p exhibited best inhibition effects against Xoo (77.85% and 62.15%, respectively) and Xac (52.51% and 36.48%, respectively) at 100 lg/mL and 50 lg/mL, which were superior to Thiodiazole-copper and Bismerthiazol. To the best of our knowledge, it is the first report on the design, synthesis, and antibacterial evaluation of novel indole-derived compounds containing 1,3,4-thiadiazole and amide moieties. [ABSTRACT FROM AUTHOR]

Ten amide compounds were isolated from Physochlaina infundibularis Kuang, of which N-[4-(acetylamino)butyl]- 3-(3,4-dihydroxyphenyl)-2-propenamide (1) was a new natural product and its structure was elucidated by comprehensive spectra data. Compounds 2–10 were isolated from Physochlaina genus for the first time. [ABSTRACT FROM AUTHOR]

In this study, we outline the eco-friendly mechanosynthesis of N-(2,2-diphenylethyl)-4-nitrobenzamide by reacting 2,2-diphenylethan-1-amine with 4-nitrobenzoyl chloride. The resulting bio-functional hybrid compound was meticulously characterized through the analysis of 1H-, 13C-NMR, UV, and detailed mass spectral analysis. [ABSTRACT FROM AUTHOR]

2-Methyl-4-oxo-4,5-dihydro-1H-pyrrole-3-carboxylic acid phenylamide was obtained as a single product in an experiment on the cyclization modes of a glycine-derived enamino amide. High yield and operational simplicity are the main features of the presented synthetic procedure. Additionally, this result extends our previous observations on the cyclization reactions of similarly functionalized enamines, by revealing the preferred cyclization pathway under Boc-deprotection conditions. [ABSTRACT FROM AUTHOR]

The title compound N-(2,4-difluorophenyl)-2-fluorobenzamide (Fo24) was synthesized in high yield (1.09 g; 87%) using standard synthetic procedures from the condensation reaction of 2-fluorobenzoyl chloride with 2,4-difluoroaniline. Crystals of Fo24 were grown from CH2Cl2 at room temperature. The Fo24 crystal structure was determined using single-crystal X-ray diffraction methods at 294 (1) K in space group Pn (No. 7). Fo24 is the second regular tri-fluorinated benzamide with the formula C13H8F3N1O1 to be reported and contrasts with the more common difluorinated and tetra-fluorinated analogues. In Fo24, both aromatic rings are effectively coplanar with an interplanar angle of 0.7(2)°. The central amide group plane is oriented by 23.04(18)° and 23.69(17)° from both aromatic rings, forming an intramolecular contact with an ortho-F12 atom with H1⋯F12 = 2.12(4) Å. The primary hydrogen bonds are 1D amide–amide interactions that form along the b-axis direction. In addition, weaker C-H⋯F/O interactions are noted: a R22(12) synthon involving two C-H, a N-H and two C-F groups, with C-F⋯C ring–ring stacking contacts completing the interactions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Guangxi Normal University - Natural Science Edition is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present study, for the first time environmentally friendly deep eutectic solvents (DESs) are used as reaction media to perform an efficient, simple and straightforward photocatalytic amide synthesis at room temperature using thioacids and amines. This method features mild conditions, a broad substrate scope, high yields (≤99%) under ambient conditions with air and moisture tolerance. Moreover, the applied operationally mild reaction conditions tolerate the presence of several different functional group substituents on the amine counterpart. Finally, the developed approach allows the recycling of the reaction medium and catalyst for at least three consecutive cycles without a significant decrease in the reaction yield. [ABSTRACT FROM AUTHOR]

N‐Carboxyanhydrides (NCAs) are compounds derived from the addition of a carboxylic acid to an isocyanate, and are known to form amides readily with the release of CO2 as a by‐product. NCAs have been known for over 120 years, but despite their lengthy history, have remained so far overshadowed by more traditional approaches to amide bond formation. In this review, the potential utility of NCAs in the context of amide bond formation is reviewed and their preparation, reactivity and practical application are also discussed. [ABSTRACT FROM AUTHOR]

A series of twenty one novel compounds derived from indole-3-acetic acid, the structure of which includes 1,3,4-thiadiazole, thioether, and amide moieties were designed, synthesized, and evaluated for their in vitro antibacterial activity against three bacterial strains. The bioassay results showed that among the synthesized compounds, N-{5-[(2-fluorobenzyl)sulfanyl]-1,3,4-thiadiazol-2-yl}-3-(1H-indol-3-yl)-propanamide demonstrated the best inhibition rate against Pseudomonas syringae pv. actinidiae and N-{5-[(4-chlorobenzyl)sulfanyl]-1,3,4-thiadiazol-2-yl}-3-(1H-indol-3-yl)propanamide possessed the best inhibition rate against Xanthomonas oryzae pv. oryzae and Xanthomonas axonopodis pv. citri, in all cases superior to that of bactericides thiodiazole copper and bismerthiazol. [ABSTRACT FROM AUTHOR]

α-Functionalized organoborons are useful building blocks and key structural elements in functional molecules. Their previous synthesis relied on the famous Matteson reaction or the late-stage borylative modification of alkynes or alkenes. Recently, the synthetic transformation of borylated building blocks offers another useful strategy and is currently actively explored. We report herein that B(MIDA)-propargylic alcohols (BPAs) are a useful type of borylated building blocks. Bearing two complementary functional group handles (alkyne and hydroxyl) in close proximity, the redox-neutral [3,3] and [2,3] sigmatropic rearrangements of BPAs allow the efficient synthesis of several types of α-functionalized boronates, including α,β-unsaturated acylborons, α-S/P-substituted allenylborons, boryl-substituted thiazoles and a borylated α,β-unsaturated hydrazine, some of which are otherwise challenging targets using other synthetic methods. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of (±)-2-chloro-N-(4-methyl-2-oxo-2H-chromen-7-yl)-2-phenylacetamide through the reaction of 7-amino-4-methyl-2H-chromen-2-one with (±)-2-chloro-2-phenylacetyl chloride. The in vitro anti-inflammatory activity of the new compound was evaluated, and the results indicated that it exhibited superior activity compared to the standard, ibuprofen. The bio-functional hybrid compound underwent thorough detailed characterization utilizing 1H and 13C NMR, UV, and mass spectral analysis.

In this study, [(N-benzamidomethyl)(N-benzoyl)amino]methyltriphenylphosphonium tetrafluoroborate was synthesized at 80 °C, starting from N-benzoylaminomethyltriphenylphosphonium tetrafluoroborate, by a specific α-amidoalkylation reaction using Hünig’s base as a catalyst. N-benzoylaminomethyltriphenylphosphonium tetrafluoroborate acts as both an amidoalkylating agent and a nucleophile precursor. The structure of the compound obtained was confirmed by spectroscopic methods (1H-, 13C-, 31P-NMR, IR) and HR-MS analysis.

Transamination of Sn(NMe2)4 with H2NMes (Mes is 2,4,6-trimethylphenyl, C9H11) led to the formation of the title compound, [Sn(C9H12N)4] or Sn(NHMes)4, which crystallizes in the tetragonal space group P\overline{4}21c, with four formula units per unit cell. The molecular structure consists of a central tin(IV) atom, which is surrounded by four NHMes groups. Sn(NHMes)4 possesses crystallographically imposed \overline{4} symmetry. The SnN4 coordination polyhedron is best described as a compressed bisphenoid.

In this work, new compounds of amide derivatives (C1-C3) were synthesized through the conversion reaction of p-chloroaniline to diazonium salt (B1), which reacts with aniline to form a new azo-compound (B3). Synthesized of p-alkoxybenzoic acid (A1-A3) and reacts with SOCl2 to form A4-A6 compounds that react with B3 compound to form amide compounds (C1-C3). The synthesized derivatives were tested by docking analysis and characterized via FTIR, 1H-NMR spectra. In the docking study, the interaction diagram also displays many van der Waals interactions, which are used to estimate the synthetic compounds' activity as insecticides like anti-termites. Heptyl came in first on the binding score, followed by octyl and then nonyl. Due to the compounds' modified conformation in interacting with the enzyme's binding pocket, the length of the alkyl residue of the derivative adversely impacted their binding inhibition. The synthesized compounds (C1 and C3) give a good result as anti-E. coli and anti-Staphylococcus strains.

Two novel bio‐based benzoxazine monomers containing imide or amide group (HPIDD‐fa and HPBA‐fa) were synthesized from raw materials of benzoyl chloride/phthalic anhydride, tyramine, furfurylamine and paraformaldehyde via a two‐step reaction. Fourier transform infrared spectroscopy (FT‐IR), proton and carbon nuclear magnetic resonance (NMR) spectroscopies were performed to characterize the structures of the benzoxazine monomers. The curing behavior was investigated by using differential scanning calorimetry (DSC) and in situ FT‐IR, and the DSC results indicate that the peak curing temperatures of HPIDD‐fa and HPBA‐fa are centered at 248.5 and 230.1°C, respectively. In addition, thermogravimetric analysis (TGA) suggests that the newly developed bio‐based benzoxazine‐derived polybenzoxazines present excellent thermal stability with Td10 (temperature at 10% weight loss) of 385 and 368°C for poly(HPIDD‐fa) and poly(HPBA‐fa), respectively. The current investigation suggests that our newly obtained bio‐based thermosetting resins are promising materials for high‐tech applications. [ABSTRACT FROM AUTHOR]

While amide‐linked covalent organic frameworks (COFs) have gained significant research attention due to their stability, there is currently no universal method for creating amide‐linked COFs with diverse chemical structures. Here, we present a gentle, precise, and versatile synthetic approach to amide‐linked COFs using N‐heterocyclic carbene (NHC)‐mediated oxidation with molecular oxygen as the oxidant. This approach is gentle and selective, and even fragile functional groups like thioethers are able to survive the transformation. Additionally, this method does not require dangerous conditions such as high pressure or strong oxidants, making it a promising way to create functional amide‐linked COFs. [ABSTRACT FROM AUTHOR]

Beckmann rearrangement has been quite successful in the preparation of many medicinally potent scaffolds. In synthetic organic chemistry, the Beckmann rearrangement is quite popular, caprolactam is synthesized from cyclohexanone oxime on a large scale for Nylon‐6 production. The function of numerous catalysts and media in the Beckmann rearrangement has been discussed in depth in this review. In the last 20 years, Beckmann rearrangement catalysis has evolved from a potentially hazardous to a more environmentally friendly catalyst, as a result of greater usage. Catalytic performance and synthetic performance of various catalytic systems have been re‐evaluated in the present review article. [ABSTRACT FROM AUTHOR]

The newly synthesized quinoxaline-1,2,4-triazole-3-amide conjugates through a multistep method. The prepared compounds were screened for their anticancer activity against secreted human cancer cell lines such as DU-145 (prostate), MCF-7 (breast), and A549 (lung) by applying the MTT method, and the standard drug etoposide was used as a reference drug. The activity results show that two compounds, namely 3,5-dimethoxy-N-(5-{[2-oxoquinoxalin-1(2H)-yl]methyl}-4H-1,2,4-triazol-3-yl)benzamide and 4-methoxy-N-(5-{[2-oxoquinoxalin-1(2H)-yl]methyl}-4H-1,2,4-triazol-3-yl)benzamide exhibited more potent activity than the standard drug. Whereas, two compounds, 3-methoxy-N-(5-{[2-oxoquinoxalin-1(2H)-yl]methyl}-4H-1,2,4-triazol-3-yl)benzamide, and 3,4-dimethoxy-N-(5-{[2-oxoquinoxalin-1(2H)-yl]methyl}-4H-1,2,4-triazol-3-yl)benzamide showed very similar activity against tested cell lines to that of the standard drug IC50 value. The in vitro tyrosine kinase EGFR inhibitory activity results indicate that two compounds, 3,5-dimethoxy-N-(5-{[2-oxoquinoxalin-1(2H)-yl]methyl}-4H-1,2,4-triazol-3-yl)benzamide and 4-methoxy-N-(5-{[2-oxoquinoxalin-1(2H)-yl]methyl}-4H-1,2,4-triazol-3-yl)benzamide exhibited more activity than the standard drug etoposide. [ABSTRACT FROM AUTHOR]

Purpose: pH enhanced (pHenh) CEST imaging combines the pH sensitivity from amide and guanidino signals, but the saturation parameters have not been optimized. We propose pHdual as a variant of pHenh that suppresses background signal variations, while enhancing pH sensitivity and potential for imaging ischemic brain injury of stroke. Methods: Simulation and in vivo rodent stroke experiments of pHenh MRI were performed with varied RF saturation powers for both amide and guanidino protons to optimize the contrast between lesion/normal tissues, while simultaneously minimizing signal variations across different types of normal tissues. In acute stroke, contrast and volume ratio measured by pHdual imaging were compared with an amide‐CEST approach, and perfusion and diffusion MRI. Results: Simulation experiments indicated that amide and guanidino CEST signals exhibit unique sensitivities across different pH ranges, with pHenh producing greater sensitivity over a broader pH regime. The pHenh data of rodent stroke brain demonstrated that the lesion/normal tissue contrast was maximized for an RF saturation power pair of 0.5 μT at 2.0 ppm and 1.0 μT at 3.6 ppm, whereas an optimal contrast‐to‐variation ratio (CVR) was obtained with a 0.7 μT saturation at 2.0 ppm and 0.8 μT at 3.6 ppm. In acute stroke, CVR optimized pHenh (i.e., pHdual) achieved a higher sensitivity than the three‐point amide‐CEST approach, and distinct patterns of lesion tissue compared to diffusion and perfusion MRI. Conclusion: pHdual MRI improves the sensitivity of pH‐weighted imaging and will be a valuable tool for assessing tissue viability in stroke. [ABSTRACT FROM AUTHOR]

Natural alkaloids originating from actinomycetes and synthetic derivatives have always been among the important suppliers of small-molecule drugs. Among their biological sources, Streptomyces is the highest and most extensively researched genus. Marine-derived Streptomyces strains harbor unconventional metabolic pathways and have been demonstrated to be efficient producers of biologically active alkaloids; more than 60% of these compounds exhibit valuable activity such as antibacterial, antitumor, anti-inflammatory activities. This review comprehensively summarizes novel alkaloids produced by marine Streptomyces discovered in the past decade, focusing on their structural features, biological activity, and pharmacological mechanisms. Future perspectives on the discovery and development of novel alkaloids from marine Streptomyces are also provided. [ABSTRACT FROM AUTHOR]