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An organocatalyzed three‐component protocol using diazoacetonitrile to access a wide range of cyanopyrazole derivatives is reported here. This strategy, which proceeds through a piperidine‐catalyzed Knoevenagel condensation/formal [3+2] cycloaddition/dehydrocyanation sequence, provides an efficient route to construct dicyanopyrazoles from aldehydes, malononitrile, and diazoacetonitrile regioselectively. Interestingly, by engaging cyanoacetate and cyanoacetamide in this protocol, we could achieve cyanopyrazole esters and carboxamides. [ABSTRACT FROM AUTHOR]

The nature of protecting group chemistry necessitates a deprotection step to restore the initially blocked functionality prior to further transformation. As this aspect of protecting group manipulation inevitably adds to the step count of any synthetic sequence, the development of methods enabling simultaneous deprotection and functionalization ("deprotective functionalization"—distinct from "deprotection followed by functionalization") is appealing, as it has the potential to improve efficiency and streamline synthetic routes. Herein, we report a deprotective functionalization of the newly introduced Nms‐amides guided by density functional theory (DFT) analysis, which exploits the inherent Nms reactivity. Mechanistic studies further substantiate and help rationalize the exquisite reactivity of Nms‐amides, as other commonly used protecting groups are shown not to exhibit the same reactivity patterns. The practicality of this approach was ultimately demonstrated in selected case studies. [ABSTRACT FROM AUTHOR]

This work presents the design, synthesis and biological activity of novel N-substituted benzimidazole carboxamides bearing either a variable number of methoxy and/or hydroxy groups. The targeted carboxamides were designed to investigate the influence of the number of methoxy and/or hydroxy groups, the type of substituent placed on the N atom of the benzimidazole core and the type of substituent placed on the benzimidazole core on biological activity. The most promising derivatives with pronounced antiproliferative activity proved to be N-methyl-substituted derivatives with hydroxyl and methoxy groups at the phenyl ring and cyano groups on the benzimidazole nuclei with selective activity against the MCF-7 cell line (IC50 = 3.1 μM). In addition, the cyano-substituted derivatives 10 and 11 showed strong antiproliferative activity against the tested cells (IC50 = 1.2–5.3 μM). Several tested compounds showed significantly improved antioxidative activity in all three methods compared to standard BHT. In addition, the antioxidative activity of 9, 10, 32 and 36 in the cells generally confirmed their antioxidant ability demonstrated in vitro. However, their antiproliferative activity was not related to their ability to inhibit oxidative stress nor to their ability to induce it. Compound 8 with two hydroxy and one methoxy group on the phenyl ring showed the strongest antibacterial activity against the Gram-positive strain E. faecalis (MIC = 8 μM). [ABSTRACT FROM AUTHOR]

The advancement of sustainable chemistry and changes in the economy are strongly intertwined. Reaction time, cost savings, moderate temperatures, and generation of the fewest byproducts are frequently achieved by using catalytic processes. Herein, we report the C−H olefination of imidazo[1,2a] pyridine carboxamides with various acrylates in the presence of Pd (OAc)2 with O2 as the oxidant in aqueous ethanol rather than using non‐ecofriendly solvents. The C−H activation features most user‐friendly reaction conditions, excellent yield as well as plenty substrate scope and applicable for C−H deuteriation of the corresponding heteroarenes with D2O. Experimental mechanistic studies indicate that C−H activation step succeeded after formation of tetra coordinated square planer Pd‐substrate adduct. [ABSTRACT FROM AUTHOR]

A series of novel carboxamide compounds containing benzoxazole motif was synthesized through multiple steps, including electrophilic substitution, cyclization, reduction and amide formation. These processes utilized ortho-aminophenol and heptafluoro-2-iodopropane as starting materials. The structures of these compounds (4a–4r) were characterized by 1H NMR, 13C NMR, and HRMS. Bioassay results revealed that most of these compounds exhibited significant insecticidal activity against Mythimna separata at 500 mg/L. Among them, compound 6-chloro-N-(4-methoxy-3-(6-(perfluoropropan-2-yl)benzo[d]oxazol-2-yl)phenyl)-N-methylnicotinamide (4r) possessed the highest activity, even at 4 mg/L. Molecular docking predicted the binding modes of 4r. These novel carboxamide compounds containing benzoxazole motifs offer valuable insights for designing insecticidal compounds targeting GABA receptors, aiming to control lepidopteran pests effectively. [ABSTRACT FROM AUTHOR]

Bicyclo[1.1.1]pentane (BCP) carboxamides are prepared from the direct addition of [1.1.1]propellane with semicarbazides in the presence of iron(II) phthalocyanine {Fe(Pc)} and tert‐butyl hydroperoxide (TBHP) in moderate to good yields. BCP ketones are also obtained under similar conditions in moderate yields. This protocol provides a straightforward one‐step access to BCP carboxamides, synthesis of which requires multiple chemical steps in previous reports. [ABSTRACT FROM AUTHOR]

Tridentate bis(carboxamide) pincers are key ligands used in catalysis, investigational medicinal inorganic compounds, and materials science. This study examined the atropisomerism of a group of bis(carboxamide) pincers with C2 symmetry to elucidate their physical, chemical, and structural behaviour, paving the way for the application of their metal complexes in different fields. One of the five compounds structurally elucidated by X-ray crystallography, 1c, has a pair of intramolecularly constrained isoquinoline ring substituents and crystallized enantiomerically pure in a chiral Sohncke space group. PM6 calculations of the 3-D potential energy surface for the main atropisomerisation reaction coordinate of 1c indicated that the lowest-energy conformer (atropisomer) has the isoquinoline rings canted out-of-plane by almost +30° and −30° relative to the central pyridine ring. The X-ray structure of 1c is located close to this energy minimum. Circular dichroism (CD) spectroscopy on bulk solid samples confirmed the presence of an excess population of one enantiomer (C2-symmetric atropisomer), most notably for compounds 1c, 1e, and 1f. CD spectra could be recorded for all compounds in solution, similarly reflecting an excess population of one atropisomer. The experimental spectra were confirmed by TD-DFT simulations at the CAM-B3LYP/def2-tzvp level of theory. We conclude that the present group of ligands are worthy of further investigation as chelating agents for metal ions with applications in chiral catalysis or biology. [ABSTRACT FROM AUTHOR]

The reaction of methyl 4-aryl(indol-3-yl)-2-pyrrolidone-3(5)-carboxylates with ammonia afforded racemic (3R*,4S*)-4-(indol-3-yl)-2-pyrrolidone-3-carboxamides and (4R*,5R*)-4-aryl-2-pyrrolidone-5-carboxamides. The three-dimensional structures of these compounds were determined by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

The design and synthesis of new chemical entities (NCEs) with suitable physicochemical properties are playing a key role in medicinal research areas. Hence, we have designed and synthesized the 10 diverse scaffolds by rightly selecting the quinoline and pyrazine to articulate carboxamide derivatives in a single‐step process with maximum conversation in a shorter time through diverse studies of Ugi multi‐component reaction. Molecular docking studies against FMS‐like tyrosine kinase‐3 (FLT3) provided well‐clustered solutions for the binding modes of these molecules and shed light on the key structural features governing the binding affinity. Two carboxamides derivatives with 3,4,5‐trimethoxy, and chloro substituents showed comparable potency in Leukemia cell lines and medium efficacy in Breast and Melanoma cancer. These results suggest that pyrazine and quinoline‐based carboxamides may be prominent as new anti‐cancer agents in chemotherapy. Additionally, in silico analysis was employed to predict the comprehensive physicochemical ADME profile (absorption, distribution, metabolism, and excretion) of the carboxamide derivatives which was proven drug‐like properties. [ABSTRACT FROM AUTHOR]

Cyanide represents a persistent threat for accidental or malicious misuse due to easy conversion into a toxic gas and access to large quantities through several industries. The high safety index of hydroxocobalamin is a cornerstone quality as a cyanide scavenger. Unfortunately, intravenous infusion of hydroxocobalamin limits the utility in a mass casualty setting. We previously reported platinum(II) [Pt(II)] complexes with trans-directing sulfur ligands as an efficacious alternative to hydroxocobalamin when delivered by a bolus intramuscular (IM) injection in mice and rabbits. Thus, to enable Pt(II) as an alternative to hydroxocobalamin, a high safety factor is needed. The objective is to maintain efficacy and mitigate the risk of nephrotoxicity. Platinum amino acid complexes with the ability to form 5- or 6-membered rings and possessing either carboxylates or carboxamides are evaluated in vitro for cyanide scavenging. In vivo efficacy wa s evaluated in the zebrafish and mice cyanide exposure models. In addition, Pt(II) complex toxicity and pharmacokinetics were evaluated in a cyanide naive Sprague Dawley model. Doses for toxicity are escalated to 5× from the efficacious dose in mice using a body surface area adjustment. The results show the carboxamide ligands display a time and pH dependence on cyanide scavenging in vitro and efficacy in vivo. Additionally, exchanging the carboxylate for carboxamide showed reduced indications of renal injury. A pharmacokinetic analysis of the larger bidentate complexes displayed rapid absorption by IM administration and having similar plasma exposure. These findings point to the importance of pH and ligand structures for methionine carboxamide complexes with Pt(II). [ABSTRACT FROM AUTHOR]

Plant diseases caused by pathogenic fungi or oomycetes seriously affect crop growth and the quality and yield of products. A series of novel 1,2,4-triazole derivatives containing carboxamide fragments based on amide fragments widely used in fungicides and the commercialized mefentrifluconazole were designed and synthesized. Their antifungal activities were evaluated against seven kinds of phytopathogenic fungi/oomycete. Results showed that most compounds had similar or better antifungal activities compared to mefentrifluconazole's inhibitory activity against Physalospora piricola, especially compound 6h (92%), which possessed outstanding activity. Compound 6h (EC50 = 13.095 μg/mL) showed a better effect than that of mefentrifluconazole (EC50 = 39.516 μg/mL). Compound 5j (90%) displayed outstanding anti-oomycete activity against Phytophthora capsici, with an EC50 value of 17.362 μg/mL, far superior to that of mefentrifluconazole (EC50 = 75.433 μg/mL). The result of molecular docking showed that compounds 5j and 6h possessed a stronger affinity for 14α-demethylase (CYP51). This study provides a new approach to expanding the fungicidal spectrum of 1,2,4-triazole derivatives. [ABSTRACT FROM AUTHOR]

[Display omitted] Isosteric replacement of the oxadiazole ring by amide bond in the structure of new non-β-lactam antibiotics led to compounds with higher activity against Gram-positive pathogens of ESKAPE panel. A series of 17 compounds were synthesized by acylation of 4-(4-fluorophenoxy)aniline with various amino acids. The spirocyclic derivative with 6-methylsulfonyl-2,6-diazaspiro[3.4]octane moiety showed excellent minimum inhibitory concentrations of 0.093–0.75 μg ml−1 against a number of methicillin-resistant Staphylococcus aureus strains. [ABSTRACT FROM AUTHOR]

The organocatalytic enolization of 2‐arylacetamides, followed by an enantioselective intramolecular conjugate addition to tethered 2,5‐cyclohexadienones, yielding 3D fused N‐heterocycles, is described. The transformation represents the first strong activating group‐free activation of carboxamides via α‐C−H deprotonation in a metal‐free, catalytic, and enantioselective reaction, and is achieved by employing a bifunctional iminophosphorane (BIMP) superbase. [ABSTRACT FROM AUTHOR]

The organocatalytic enolization of 2‐arylacetamides, followed by an enantioselective intramolecular conjugate addition to tethered 2,5‐cyclohexadienones, yielding 3D fused N‐heterocycles, is described. The transformation represents the first strong activating group‐free activation of carboxamides via α‐C−H deprotonation in a metal‐free, catalytic, and enantioselective reaction, and is achieved by employing a bifunctional iminophosphorane (BIMP) superbase. [ABSTRACT FROM AUTHOR]

A single-site Fe(III) carboxamide complex, [Fe(HbpH) (Cl) 2 ] (1), (HbpH‾ = N,N′-Bis(picolinoyl)hydrazine) anion), was synthesized and used as the electrocatalyst of water oxidation reaction. Complex 1 catalyzes the oxidation of water to O 2 at the pH of 8 in phosphate buffer solution with the onset of a catalytic wave at about 0.45 V versus RHE with the turnover frequency (TOF) of 5.8 s−1 at room temperature. The stability of the catalyst in water oxidation processes by electrochemical and UV–vis measurements, demonstrated the realistic molecular electrocatalysis of 1. Differential pulse voltammetry (DPV) of 1 in different pH values showed the dependency of oxidation potential to the pH of the environment, establishing the fact that the catalytic cycle involves the proton-coupled electron transfer (PCET) process. Density functional theory (DFT) calculations on the mechanism of water oxidation process of 1 shows that the oxygen evolution reaction is carried out through the water nucleophilic attack (WNA) to the metal center ion, resulted to the formation of FeIV(O) species. Also, DFT calculations showed that the formation of an O–O bond proceeds through the interaction two molecular mechanism (I2M), which compete with the WNA mechanism following from experimental analysis. The electroactivity of the metal centre and carboxamide ligand and the ability of the ligand to stabilize the high oxidation numbers of the metal-ion centre during the oxidation process, provide different oxidation pathways for an OER process. • Synthesis of carboxamide Fe(III) complex using ionic liquid as an environmentally benign reaction medium. • Electrocatalytic studies of the [Fe(HbpH) (Cl) 2 ] (1) in the OER process. • TOF values of 5.8 mol of hydrogen in each mole of catalyst per second for the catalyst 1. • The I2M mechanism competes with the WNA mechanism investigation using DFT calculations in OER process. [ABSTRACT FROM AUTHOR]

In the present work, several coumarin-3-carboxamides with different azacrown ether moieties were designed and tested as potential luminescent sensors for metal ions. The derivative containing a 1-aza-15-crown-5 as a metal chelating group was found to yield the strongest response for Ca2+ and Pb2+, exhibiting an eight- and nine-fold emission increase, respectively, while other cations induced no changes in the optical properties of the chemosensor molecule. Job's plots revealed a 1:1 binding stoichiometry, with association constants of 4.8 × 104 and 8.7 × 104 M–1, and limits of detection of 1.21 and 8.04 µM, for Ca2+ and Pb2+, respectively. Computational studies suggest the existence of a PET quenching mechanism, which is inhibited after complexation with each of these two metals. Proton NMR experiments and X-ray crystallography suggest a contribution from the carbonyl groups in the coumarin-3-carboxamide fluorophore in the coordination sphere of the metal ion. [ABSTRACT FROM AUTHOR]

A nickel-catalyzed hydrogen isotope exchange has been developed with acetone-d6 as the deuterium source. The reaction showed an improved kinetic feature of H/D exchange under the assistance of 2-pyridones, efficiently affording regioselective labeled aryl and alkyl carboxamides. [ABSTRACT FROM AUTHOR]

Borane-pyridine acts as an efficient (5 mol%) liquid catalyst, providing improved solubility for the direct amidation of a wide range of aromatic and aliphatic carboxylic acids and amines to form secondary and tertiary carboxamides. Tolerance of potentially incompatible halo, nitro, and alkene functionalities has been demonstrated. [ABSTRACT FROM AUTHOR]

In this work, the privileged scaffold of 4-hydroxy-2quinolinone is investigated through the synthesis of carboxamides and hybrid derivatives, as well as through their bioactivity evaluation, focusing on the ability of the molecules to inhibit the soybean LOX, as an indication of their anti-inflammatory activity. Twenty-one quinolinone carboxamides, seven novel hybrid compounds consisting of the quinolinone moiety and selected cinnamic or benzoic acid derivatives, as well as three reverse amides are synthesized and classified as multi-target agents according to their LOX inhibitory and antioxidant activity. Among all the synthesized analogues, quinolinone–carboxamide compounds 3h and 3s, which are introduced for the first time in the literature, exhibited the best LOX inhibitory activity (IC50 = 10 μM). Furthermore, carboxamide 3g and quinolinone hybrid with acetylated ferulic acid 11e emerged as multi-target agents, revealing combined antioxidant and LOX inhibitory activity (3g: IC50 = 27.5 μM for LOX inhibition, 100% inhibition of lipid peroxidation, 67.7% ability to scavenge hydroxyl radicals and 72.4% in the ABTS radical cation decolorization assay; 11e: IC50 = 52 μM for LOX inhibition and 97% inhibition of lipid peroxidation). The in silico docking results revealed that the synthetic carboxamide analogues 3h and 3s and NDGA (the reference compound) bind at the same alternative binding site in a similar binding mode. [ABSTRACT FROM AUTHOR]

Succinate dehydrogenase (SDH, EC 1.3.5.1) is one of the most promising targets for fungicide development and has attracted great attention worldwide. However, existing commercial fungicides targeting SDH have led to the increasingly prominent problem of pathogen resistance, so it is necessary to develop new fungicides. Herein, we used a structure-based molecular design strategy to design and synthesize a series of novel SDHI fungicides containing an N-(alkoxy)diphenyl ether carboxamide skeleton. The mycelial growth inhibition experiment showed that compound M15 exhibited a very good control effect against four plant pathogens, with inhibition rates of more than 60% at a dose of 50 μg/mL. A structure–activity relationship study found that N-O-benzyl-substituted derivatives showed better antifungal activity than others, especially the introduction of a halogen on the benzyl. Furthermore, the molecular docking results suggested that π–π interactions with Trp35 and hydrogen bonds with Tyr33 and Trp173 were crucial interaction sites when inhibitors bound to SDH. Morphological observation of mycelium revealed that M15 could inhibit the growth of mycelia. Moreover, in vivo and in vitro tests showed that M15 not only inhibited the enzyme activity of SDH but also effectively protected rice from damage due to R. solani infection, with a result close to that of the control at a concentration of 200 μg/mL. Thus, the N-(alkoxy)diphenyl ether carboxamide skeleton is a new starting point for the discovery of new SDH inhibitors and is worthy of further investigation. [ABSTRACT FROM AUTHOR]

The Cp*Co(III) C−H allylation of (hetero)arenes with allyl aryl ethers has been developed using an amide as directing group (24 examples). DFT calculations have shed light on the mechanistic course and reactivity pattern, showing that strong electron releasing groups favour the reaction by reducing the activation barrier of the rate‐determining C−H activation step. However, the steric strain can increase the energy of the migratory insertion step to the point of completely preventing the reaction, as in the case of the 3,5‐dimethylbenzamide. The obtained allylated compounds have been transformed into a variety of interesting heterocyclic and carbocyclic structures, such as isoquinolones and isochromanones. [ABSTRACT FROM AUTHOR]

Despite remarkable successes in linear and branched vinyl (hetero) arene synthesis, regiodivergent C−H olefination with a single catalytic system has remained underdeveloped. Overcoming this limitation, a Pd/MPAA‐catalyzed regiodivergent C−H olefination of imidazo[1,2a] pyridine carboxamides with unactivated terminal alkenes to generate branched and linear olefinated products depending upon the electronic nature of alkenes is reported herein. Moreover, this protocol can be applied for C−H deuteriation of the corresponding heteroarenes with D2O as deuterium source. Preliminary experimental studies combined with computational investigations (DFT studies) suggest that regiodivergent olefination can be controlled by olefin insertion and β‐hydride elimination steps. [ABSTRACT FROM AUTHOR]

Direct synthesis of Pyridine-2,6-dicarboxylic a-+cid bis-(3-hydroxy phenyl)]amide, (Pydca), chelating ligand was applied for Th(IV) extraction from Abu Rusheid Ore Sample, South Eastern Desert, Egypt, between latitudes 24° 37ʹ 16ʹʹ N and longitudes 34° 46 ʹ 35 ʹʹ E and far from the Red Sea coast by about 42 km west, using poly phosphoric acid catalyst (PPA). The synthesis of new amide via direct condensation of organic acid and aromatic amine was performed in DMF at 100°C. The immediate condensation reaction led to construct the carboxamide derivative in one easy step dismantling the hard activation, halogenation, step resulting in a good yield production. This cross-coupling reaction appears simple, convenient and has a wide scope of activities. This protocol could be extended to industrial large-scale production processes. Experimental measurements have been optimised such as diluent type, pH, contact time, initial Th(IV) concentration, temperature, pydca conc., co-existing ions and stripping agents. It was found that a maximum value of Th(IV) retention (0.86 × 10−3 mol/L) is observed with 0.015 mol/L pydca/CCl4 chelating ligand at room temperature. From kinetic aspects, it was found that Th(IV) extraction follows the pseudo-first order kinetic model. The thermodynamic parameters, ΔS, ΔH and ΔG were also evaluated indicating an endothermic and spontaneous extraction process with increasing the randomness of the extraction system. Th(IV) can be completely back extracted from the loaded pydca chelating ligand using 0.5 M HNO3, 1 M H2SO4 and 1 M HCl. Finally, the optimised factors have been applied for Th(IV) recovery from Abu Rusheid Ore Sample, South Eastern Desert, Egypt, producing a thorium oxide concentrate with Th(IV) content of 81.43% with a purity of 92.67%. [ABSTRACT FROM AUTHOR]

Herein, we present the first metallomacrocyclic Mn(II) complexes as efficient catalysts for the transfer hydrogenation of ketones. The dinuclear Mn(II) complexes [Mn2(L1–L4)2Cl2] (Mn1–Mn4), were synthesised in good yields by reacting MnCl2 ⋅ 4H2O with the ligands N,N′‐(1,4‐phenylene)dipicolinamide (L1), N,N′‐(1,2‐phenylene)dipicolinamide (L2), N,N′‐(4‐methoxy‐1,2‐phenylene)dipicolinamide (L3) and N,N′‐(4,5‐dimethyl‐1,2‐phenylene)dipicolinamide (L4). Structural characterization of the resulting Mn(II) complexes was achieved using FT‐IR spectroscopy, mass spectrometry, magnetic moment measurements, elemental analysis, and single‐crystal X‐ray diffraction for Mn2. The solid‐state structure of complex Mn2 reveals a dinuclear Mn(II) core, in which the metal coordination sphere consists of two bidentate, K2(N−O) bridging L2 units and two chlorido ligands to give a distorted octahedral geometry. The Mn(II) complexes (Mn1–Mn4) were quite active catalysts for the transfer hydrogenation of ketones displaying turnover numbers (TON) of up to 2633, which is comparable to those of well‐established Mn(I) catalysts. The new Mn(II) complexes also efficiently hydrogenated a number of aromatic, heterocyclic, functionalized and aliphatic ketones. More significantly, cheaper, and readily available hydrogen sources like ethanol also gave decent catalytic activities in the transfer hydrogenation reactions. [ABSTRACT FROM AUTHOR]

Highly enantio‐ and diastereoselective (Ipc)2BOTf mediated aldol reactions of morpholine carboxamides are described. A wide variety of α‐substituted N‐acyl morpholine carboxamides were successfully employed, including α‐bromo, α‐chloro, α‐vinyl and para‐methoxyphenyl morpholine carboxamides which provided the corresponding aldol products in moderate to excellent yields, and generally with high enantio‐ and diastereoselectivities. [ABSTRACT FROM AUTHOR]

As part of our continuous efforts to discover novel c-Met inhibitors as antitumor agents, four series of thiazole/thiadiazole carboxamide-derived analogues were designed, synthesised, and evaluated for the in vitro activity against c-Met and four human cancer cell lines. After five cycles of optimisation on structure–activity relationship, compound 51am was found to be the most promising inhibitor in both biochemical and cellular assays. Moreover, 51am exhibited potency against several c-Met mutants. Mechanistically, 51am not only induced cell cycle arrest and apoptosis in MKN-45 cells but also inhibited c-Met phosphorylation in the cell and cell-free systems. It also exhibited a good pharmacokinetic profile in BALB/c mice. Furthermore, the binding mode of 51am with both c-Met and VEGFR-2 provided novel insights for the discovery of selective c-Met inhibitors. Taken together, these results indicate that 51am could be an antitumor candidate meriting further development. [ABSTRACT FROM AUTHOR]

This contribution described the chemoselective reduction of secondary carboxamides to aldimines. To perform such challenging transformation, we reported a catalyzed hydrosilylation using Fe(CO)4(IMes) [IMes=1,3‐bis (2,4,6‐trimethylphenyl) imidazol‐2‐ylidene] as the catalyst, diphenylsilane as the reductant under UV irradiation (350 nm) at room temperature for 16 h. Aldimines were then obtained, after a basic quench, in 32–83 % isolated yields. This transformation was unprecedented at iron. [ABSTRACT FROM AUTHOR]

Seven-coordinate rhenium oxo complexes supported by a tetradentate bipyridine carboxamide/carboxamidate ligand are reported. The neutral dicarboxamide H2Phbpy-da ligand initially coordinates in an L4 (ONNO) fashion to an octahedral rhenium oxo precursor, yielding a seven-coordinate rhenium oxo complex. Subsequent deprotonation generates a new oxo complex featuring the dianionic (L2X2) carboxamidate (NNNN) form of the ligand. Computational studies provide insight into the relative stability of possible linkage isomers upon deprotonation. Structural studies and molecular orbital theory are employed to rationalize the relative isomer stability and provide insight into the rhenium–oxo bond order. [ABSTRACT FROM AUTHOR]

5-Arylisoxazolyl- and 4,5-dichloroisothiazolyl-3-carboxamides were synthesized based on trichlorethylene and its dimer. The prepared carboxamides were used for the synthesis of azanediylbisisoxazolyl(isothiazolyl)carboxamides and bis(azolyl)carboxamides. The new polynitrogen ligands form palladium complexes LPdCl2, which exhibit high catalytic activity in cross-coupling reactions in water media in organic solvent-free conditions. [ABSTRACT FROM AUTHOR]

Naegleria fowleri is a free-living thermophilic flagellate amoeba that causes a rare but life-threatening infection called primary amoebic meningoencephalitis (PAM), with a very high fatality rate. Herein, the anti-amoebic potential of carboxamide derivatives possessing sulfonyl or sulfamoyl moiety was assessed against pathogenic N. fowleri using amoebicidal, cytotoxicity and cytopathogenicity assays. The results from amoebicidal experiments showed that derivatives dramatically reduced N. fowleri viability. Selected derivatives demonstrated IC50 values at lower concentrations; 1j showed IC50 at 24.65 μM, while 1k inhibited 50% amoebae growth at 23.31 μM. Compounds with significant amoebicidal effects demonstrated limited cytotoxicity against human cerebral microvascular endothelial cells. Finally, some derivatives mitigated N. fowleri-instigated host cell death. Ultimately, this study demonstrated that 1j and 1k exhibited potent anti-amoebic activity and ought to be looked at in future studies for the development of therapeutic anti-amoebic pharmaceuticals. Further investigation is required to determine the clinical relevance of our findings. [ABSTRACT FROM AUTHOR]

The combination of two neutral CHON reagents, a lipophilic phenanthroline dicarboxamide and a hydrophilic diglycolamide, resulted in a synergistic separation of adjacent light lanthanides in nitrate medium as the ligands present a reversed lanthanide selectivity. Separation factors higher than 7 were obtained for the pair Pr/Nd, which is one of the highest values reported in the literature. [ABSTRACT FROM AUTHOR]

2-Oxo-4-cyano-1,2-dihydropyridine-3-carboxamides were synthesized. Their antiproliferative activity was studied. They were shown to inhibit slightly the growth of cell lines of lung cancer (a more pronounced tendency for lines A549/ATCC, NCI-H522, and HOP-62); colon cancer (more pronounced for line HCC-2998); brain cancer (for line SNB-19), melanoma (for lines UACC-62, SK-MEL-2, and MALME-3M); kidney cancer (for lines A498 and UO-31); and breast cancer (for lines HS 578T and T-47D). [ABSTRACT FROM AUTHOR]

The antifungal activity of ten new silver salts of pyrrolo[3,4-c]pyrazol-3-ones and pyrazole-3-carboxamides containing sulfamide groups was studied. Data from in vitro studies and computer predictions of their biological activity were compared. The pharmacophores affecting the antifungal activity were identified. The compound with a 4-ethoxyphenyl substituent in the heterocycle 5-position exhibited the most pronounced antifungal effect (including against Candida non-albicans species) that exceeded the activity of the reference drugs by two times and more (MIC50 = 1.0 mg/L, MIC90 = 15.6 mg/L). This gave grounds for further study of the mechanisms of the revealed antimycotic activity. [ABSTRACT FROM AUTHOR]

Sulfonamide-based carboxamide drugs have multiple active sites that confers them with a variety of chemical and pharmacological activities. The combination of structural functionalities has been established to be vital in the drug discovery process. The synthesis of novel, nontoxic, cheap and effective anti-parasitic analogues is a trending aspect of pharmaceutical and medicinal chemistry research. In this research, the synthesis, characterization, and density functional theory (DFT) investigation of the reactivity and anti-trypanosomal simulation of benzenesulphonamide-based carboxamide derivatives was carried out for 2-[N-(benzenesulfonyl)-1-phenylformamido]-N-(4-nitrophenyl)acetamide(BPNA), 2-[N-(benzenesulfonyl)-1-phenylformamido]-N-(4-nitrophenyl)-3-phenylpropanamide (BPNPP), 2-[N-(benzenesulfonyl)-1-phenylformamido]-3-(1H-indol-2-yl)-N-(4-nitrophenyl)propenamide (BPINP) and 2-[N-(benzenesulfonyl)-1-phenylformamido]-4-methyl-N-(4-nitrophenyl)pentanamide (BPMNP) following an environmentally friendly zinc chloride catalyst mediated synthesis. The lower value of the HOMO-LUMO energy gap (2.9756 eV) observed for BPMNP indicated its higher chemical and biological activity. The global electrophilicity index (ω), which is related to chemical hardness and chemical potential in line with other global descriptors showed that the order of reactivity is BPMNP > BPINP > BPNPP > BPNA. The NBO analysis showed that σ → σ*, σ* →π*, π → π*, and π* → π* transitions were observed in all the compounds while σ → σ* and π* → π* showed the lowest and the highest stabilization energy, respectively. From the molecular docking analysis, BPMNP again, showed the most stable binding energy of − 9.6 kcal/mol and bond length of 1.99 Å, evidently performing better than the standard drug with binding energy and bond length of −7.6 kcal/mol and 2.89 Å, respectively. The binding energy obtained was observed to follow a decreasing order as thus; BPMNP > BPINP > BPNA > BPNPP which strongly indicates alkane-substituted benzenesulphonamide carboxamides especially BPINP and BPMNP possess potent curative properties against trypanosomiasis. [ABSTRACT FROM AUTHOR]

The quinoxaline-5-carboxamide derivatives (Vq–Vu) and (VIa–Vu) were prepared using methyl-2,3-diamino benzoate as the starting material. Analytical and spectral data were used to characterize the synthesized compounds. Four bacterial strains—Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pyogenes—were tested with titled compounds. Fluoro-substituted, phenethyl groups, oxygenated cyclic and aliphatic, and benzonitrile are among the reported derivatives that demonstrated good inhibition for antibacterial activity, while the rest compounds shown equipotent to moderate action. Using commercially available 2,3-diamino benzoate 1 as the starting material, innovative 2,3-dimethoxyquinoxaline-5-carboxamide derivatives (Vq–Vu) and 2,3-dihydroyquinoxaline-5-carboxamide derivatives (VIa–VIu) were synthesised in five stages. The electronegative group on the quinoxaline moiety boosts the antibacterial properties of the produced compounds, according to the results of SAR. [ABSTRACT FROM AUTHOR]

Forensic toxicology laboratories often encounter casework backlogs, which raise concerns for drug stability that can be affected by long storage times, temperature and preservatives, or the lack thereof. The focus of this research was to evaluate the impact of these factors on the stability of 17 synthetic cannabinoids (SCs) in human whole blood and 10 associated metabolites in human urine. The fortified biological specimens were stored under room temperature (20°C), refrigerator (4°C) and freezer (–20°C) conditions for a period of 52 weeks. Preservatives included potassium oxalate, sodium ethylenediaminetetraacetic acid and sodium fluoride. Extraction of analytes was conducted using supported liquid extraction and analyzed using a liquid chromatograph-tandem mass spectrometer. Under all three storage conditions, the majority of urine metabolites were stable up to 9 weeks. All analytes in frozen sodium fluoride–preserved blood were stable at 21–52 weeks with the exception of APP-PICA. Analytes in the blood that were stable up to 52 weeks in the freezer generally had a core structure of a carbonyl substituent on a pyrazole or pyrrole with surrounding nonpolar groups. In contrast, compounds with two adjacent polar carbonyl functional groups experienced degradation at ≤1 week under ambient temperature and refrigeration. 5-Fluoropentyl analogs, XLR11 and 5-fluoro ADB-PINACA, in comparison to their counterpart analytes, UR144 and ADB-PINACA, were unstable at earlier time points under all temperatures. Based on these data, forensic blood evidence suggesting the presence of SC compounds is recommended to be frozen with sodium fluoride and potassium oxalate preservatives for optimal quantitative results. [ABSTRACT FROM AUTHOR]

Using ab-initio molecular simulations we have detected an asymmetric vibrational activation effect in N-methyl acetamide. The effect is generated by a favorable disposition of the orthogonal σ–π system present in the carboxamide moiety of N-methyl acetamide, so when the CO site is perturbed, it generates a charge oscillation in the molecule which produces a general vibrational activation in the molecule. Meanwhile, the NH bond stretching does not generate a charge oscillation precluding the vibrational molecular activation which traps the vibrational energy in this specific site of the carboxamide moiety of the N-methyl acetamide molecule. [ABSTRACT FROM AUTHOR]

5-Chloro-N-((2-oxo-3-(4-(3-oxomorpholino) phenyl) oxazolidin-5-yl) methyl) thiophene-2-carboxamide derivatives were synthesized in a simple and efficient approach using 2-(oxiran-2-ylmethyl) isoindoline-1, 3-dione, 4-(4-aminophenyl) morpholin-3-one, and 5-chlorothiophene-2-carbonyl chloride by stepwise synthesis. Three compounds 3, 4 and 7 were designed, prepared, and screened for anticancer activity against HeLa, MCF- 7, A-549 and K-562 and antibacterial activities against Gram +ve and Gram -ve strains. The carboxamide moieties proved to be capable for the development of new anticancer and anti-bacterial agents. Docking studies carried out on target receptors caspase-3 HeLa cell line and Staphylococcus aureus DNA-Gyrase also supported the anticancer and antimicrobial activity of compounds 3, 4 and 7. [ABSTRACT FROM AUTHOR]

This study presents the synthesis, characterization, and antimicrobial efficacy of a novel pyrazoline carboxamide heterocyclic compound. Synthesized through a two-step process, involving the formation of an α,β-unsaturated ketone and subsequent conversion into a pyrazoline carboxamide derivative, the compound's structure and functional groups were confirmed using FT-IR, 1H NMR, and DEPT-135 techniques. The compound demonstrated high purity and yield, displaying significant inhibitory zones against microorganisms, notably Listeria monocytogenes (14.2 ± 0.0 mm to 16.8 ± 1.3 mm) and Candida albicans (10.9 ± 0.6 mm to 17.8 ± 1.5 mm). Evaluation of drug-likeness and toxicity highlighted its potential for drug development. Molecular docking studies indicated strong binding affinities to key antimicrobial target proteins, including DNA gyrase, penicillin-binding protein, and C. albicans sterol 14-a-demethylase. Molecular dynamics simulations revealed the compound's structural flexibility. These results make this new compound a candidate for further exploration in drug development, highlighting its potential therapeutic applications. [ABSTRACT FROM AUTHOR]

Diabetes is a chronic metabolic disorder of the endocrine system characterized by persistent hyperglycemia appears due to the deficiency or ineffective use of insulin. The glucose level of diabetic patients increases after every meal and medically recommended drugs are used to control hyperglycemia. Alpha-glucosidase inhibitors are used as antidiabetic medicine to delay the hydrolysis of complex carbohydrates. Acarbose, miglitol, and voglibose are commercial drugs but patients suffer side effects of flatulence, bloating, diarrhea, and loss of hunger. To explore a new antidiabetic drug, a series of benzotriazinone carboxamides was synthesized and their alpha-glucosidase inhibition potentials were measured using in vitro experiments. The compounds 14k and 14l were found to be strong inhibitors compared to the standard drug acarbose with IC50 values of 27.13 ± 0.12 and 32.14 ± 0.11 μM, respectively. In silico study of 14k and 14l was carried out using molecular docking to identify the type of interactions developed between these compounds and enzyme sites. Both potent compounds 14k and 14l exhibited effective docking scores by making their interactions with selected amino acid residues. Chemical hardness and orbital energy gap values were investigated using DFT studies and results depicted affinity of 14k and 14l towards biological molecules. All computational findings were found to be in good agreement with in vitro results. [ABSTRACT FROM AUTHOR]

A non-traditional approach for the synthesis of pyrrole carboxamides from pyrrole carboxaldehyde and formamides or amines with catalytic amounts of nBu4NI and TBHP as oxidants is reported herein. The method is operationally simple providing straightforward access to primary, secondary, and tertiary pyrrole carboxamides in good to excellent yields utilizing inexpensive reagents under mild conditions. Unlike traditional amidations that involve ionic reactions, a mechanistic study of our current method unveils the involvement of 2- or 3-pyrrole acyl radicals that are otherwise rarely postulated. The applicability of the current method is further demonstrated in the synthesis of a drug-like compound, i.e., an optically pure carboetomidate amide. [ABSTRACT FROM AUTHOR]

The reaction of maleopimaric acid and its acid chloride with 3-, 6-, and 8-aminoquinolines afforded quinoline containing maleopimarimides and carboxamides in high yields, respectively. Structure of the synthesized compounds was determined by 1Н, 13С, 1H–13C HSQC, 1H–13C HMBC, COSY, NOESY, and 1Н–15N HMBC NMR spectroscopy methods. [ABSTRACT FROM AUTHOR]

Novel and efficient fluorescent probes having N2, N6-bis(5-Mercapto-1,3,4-thiadiazol-2-yl)pyridine-2,6-dicarboxamide (TPDC) are synthesized by the condensation reaction between pyridine-2,6-dicarboxylic acid and amino derivatives of thiadiazoles. The novel fluorescent probe TPDC exhibits a highly sensitive and selective response to Fe3+ and Hg2+ ions in HEPES buffer solution showing the detection limit to be 0.49 μM and 0.0066 μM, respectively. The binding stoichiometry of TPDC with Fe3+ and Hg2+ have been estimated by Jobs plot and found to be 1:1. These have been confirmed by MS spectra. The stability constant of the fluorescent probe with Fe3+ and Hg2+ has been determined by the Benesi-Hildebrand equation. The binding constant for Fe3+ and Hg2+ ions are 2.54 × 10¹ M-1 and 0.18 × 10² M-1, respectively. The crystallinity of compounds have also been calculated by XRD spectra and found to be 66.37%. [ABSTRACT FROM AUTHOR]

A series of novel botanical active component 4-chromanone derivatives incorporating carboxamide and 1,3,4-thiadiazole thioether moieties were synthesized and evaluated for their in vitro antibacterial and activities antifungal against Xanthomonas axonopodis pv. citri (Xac), Xanthomonas oryzae pv. oryzicolaby (Xoc) and Mucor bainieri (M. bainieri), Mucor fragilis (M. fragilis), Trichoderma atroviride (T. atroviride), respectively. Antibacterial screening results suggested that the target compounds showed moderate to good antibacterial activities against Xac and Xoc, to the contrary, had lower inhibitory effects on M. fragilis, M. bainieri, and T. atroviride. Among the target compounds, compound 6-chloro-N-(5-(methylthio)-1,3,4-thiadiazol-2-yl)-4-oxochromane-2-carboxamide (6f) had the best inhibition rates against Xac (85.15% and 72.41%, respectivelty) and Xoc (95.14% and 82.09%) at 200 and 100 μg/mL, which were superior to Bismerthiazol and Thiodiazole copper. As far as we know, it is the first report on the design, synthesis, and bioactivity evaluation of novel 4-chromanone-derived compounds incorporating carboxamide and 1,3,4-thiadiazole thioether moieties. [ABSTRACT FROM AUTHOR]

Herein we reported an efficient photoredox‐catalyzed reaction for site‐selective C(sp3)−H functionalization of carboxamides with silyl enol ethers as radical acceptors. The reaction proceeded through amidyl radical‐directed 1,5‐hydrogen atom transfer (1,5‐HAT) and C(sp3)−C(sp3) bond formation via radical addition of silyl enol ethers. The process features mild conditions and high functional‐group tolerance, allowing the preparation of a series of carboxamides with pendant carbonyl moieties. [ABSTRACT FROM AUTHOR]

A series of 1-[2-(4-methyl-2-(methylthio)pyrimidine-5-carboxamido)phenyl]ethyl-substitutedphenyl carbamates (3a–3i) were designed and synthesized, using 4-methyl-2-(methylthio)pyrimidine-5-carboxylic acid, (2-aminophenyl)ethan-1-one, and substituted phenyl isocyanates as starting materials. Their structures were characterized by 1H NMR, 13C NMR, IR and HRMS. The in vitro fungicidal activities against Sclerotinia sclerotiorum were evaluated, and the result showed that some compounds displayed moderate antifungal activity with >60% inhibitory rates, among which 1-[2-(4-methyl-2-(methylthio)pyrimidine-5-carboxamido)phenyl] ethyl-(2- methyl phenyl)carbamate (3a) and 1-[2-(4-methyl-2-(methylthio)pyrimidine-5- carboxamido)phenyl] ethyl-(3-trifluoromethyl phenyl)carbamate (3g) held inhibitory rates of 69.5% and 70.3% at 100 mg/L, respectively. Molecular docking study showed that 3g can form two hydrogen bonds and a cation-π interaction with succinate dehydrogenase. [ABSTRACT FROM AUTHOR]

Universal divergent approaches to 1,2,3-triazole-fused quinazolinones and benzoxazine imines have been developed. Both utilize the intramolecular base-mediated cyclization of readily available 2-(5-iodotriazolyl)benzamides. While the O-attack by an ambident carboxamide anion, leading to the formation of cyclic imidates, requires only the presence of a base in a non-polar solvent, the N-attack proceeds as Cu-catalyzed Ullmann coupling. The developed protocols for chemoselective cyclization are operationally simple and cost-efficient, and feature a good functional group compatibility and a much broader scope in comparison with the previously reported approaches. [ABSTRACT FROM AUTHOR]

Concerning environmentally benign catalysis with reduced chemical usage, less energy consumption, and waste minimization, metal–organic frameworks (MOFs) with spatially isolated task-specific functionalities not only execute atom-economic important reactions but also enable size-exclusive catalysis at the interface of structure–function synergy. Herein, we synthesized a bipillar-layer Co(II) MOF from the dicarboxylate ligand and carboxamide moiety grafted pyridyl linker. The framework contains a [Co2(COO)4N4] secondary building unit (SBU) and shows excellent hydrolytic stability due to ample non-covalent interactions among the highly conjugated aromatic struts. Notably, the carboxamide functionalities remain free and are perfectly positioned throughout the one-dimensional channels of the framework, wherein three-fold interpenetration of the structure largely increases their density along the pore wall. Benefiting from these structural features, the activated MOF acts as an unprecedented organocatalyst in tandem deacetalization-Knoevenagel condensation towards electronically assorted substrates that were additionally characterized using single-crystal X-ray diffraction. Importantly, the reaction occurs under solvent-free mild conditions, and high catalyst reusability is recorded. In this one-pot cascade reaction, substrates with molecular dimensions larger than that of the three-fold interpenetration generated optimized pore-aperture undergo insignificant conversion, and therefore a rare molecular-dimension-induced size-selectivity is demonstrated. The catalytic route is detailed based on a battery of control experiments, including juxtaposing the performance of an isostructural MOF without any linker functionalization. Compared to the common Lewis acid mediated route, the results explicitly corroborate the first-ever substrate activation via hydrogen bonding to prepare coumarin derivatives via a tandem pathway, and shed light on this futuristic unconventional catalysis using contemporary materials and avoiding major operative glitches. [ABSTRACT FROM AUTHOR]

New derivatives of 3-methylcytisine with 9-aromatic substituents bonded to the pyridone core of the starting alkaloid through spacers of various natures, e.g., aminomethyl, amide, thio- and carboxamide, ethenyl, and ethyl, were synthesized from 9-amino- and 9-bromo-2-oxomethylcytisine. [ABSTRACT FROM AUTHOR]