Title Compounds Research Articles

Design of new α-glucosidase inhibitors based on the bis-4-hydroxycoumarin skeleton: Synthesis, evaluation, and in silico studies

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

Encapsulating Nickel-Iron Alloy Nanoparticles in a Polysilazane-Derived Microporous Si-C-O-N-Based Support to Stimulate Superior OER Activity.

The in situ confinement of nickel (Ni)-iron (Fe) nanoparticles (NPs) in a polymer-derived microporous silicon carboxynitride (Si-C-O-N)-based support is investigated to stimulate superior oxygen evolution reaction (OER) activity in an alkaline media. Firstly, we consider a commercial polysilazane (PSZ) and Ni and Fe chlorides to be mixed in N,N-dimethylformamide (DMF) and deliverafter overnight solvent reflux a series of Ni-Fe : organosilicon coordination polymers. The latter are then heat-treated at 500 °C in flowing argon to form the title compounds. By considering a Ni : Fe ratio of 1.5, face centred cubic (fcc) NixFey alloy NPs with a size of 15-30 nm are in situ generated in a porous Si-C-O-N-based matrixdisplaying a specific surface area (SSA) as high as 237 m2 ⋅ g-1. Hence, encapsulated NPs are rendered accessible to promote electrocatalytic water oxidation. An OER overpotential as low as 315 mV at 10 mA ⋅ cm-2 is measured. This high catalytic performance (considering that the metal mass loading is as low as 0.24 mg cm-2) is rather stable as observed after an activation step; thus, validating our synthesis approach. This is clearly attributed to both the strong NP-matrix interaction and the confinement effect of the matrix as highlighted through post mortem microscopy observations.

Synthesis of 2‐Aminopyridine Derivatives via a Tandem CuAAC/Ring‐Cleavage/[4+2]‐Cycloaddition/Rearrangement Reaction Sequence

Abstract2H‐Azirines are an important class of small‐ring heterocycle that have been employed as versatile synthetic building blocks. Herein, a one‐pot CuAAC/ring‐cleavage/[4+2]‐cycloaddition/rearrangement reaction sequence involving terminal ynones, sulfonyl azides and 2H‐azirines is reported that leads to 2‐aminopyridine derivatives. In the first step, highly reactive N‐sulfonyl α‐acylketenimines are generated, via a CuAAC/ring‐cleavage process, from sulfonyl azides and terminal ynones and these undergo inverse electron‐demand Diels–Alder cycloaddition reactions with 2H‐azirines to form (isolable) 1,3‐oxazines that themselves undergo base‐promoted ring‐cleavage and rearrangement reactions to afford the title compounds.

Mer-[Ni(dien)2]Cl2.H2O and mer-[Ni(dien)2](NO3)2 complexes (dien= diethylenetriamine): Synthesis, physical, computational studies, antioxidant activity, and their use as precursors for Ni/NiO nanoparticles’ preparation

Two new Ni(II) complexes, mer-[Ni(dien)2]Cl2.H2O (I) and mer-[Ni(dien)2](NO3)2 (II), where dien= diethylenetriamine and mer refers to meridional coordination, have been prepared under ambient conditions. Complex (I) crystallizes in the P21/c space group of the monoclinic system, with a = 13.5000(4) Å, b = 8.7170(3) Å, c = 13.9430(4) Å, β = 102.091(2)° and V = 1604.41 Å3, whereas complex (II) crystallizes in the Pbca space group of the orthorhombic system, with a = 8.8117(6) Å, b = 14.0023(8) Å, c = 26.7603(17)Å and V = 3301.79 Å3. Both structures contain the [Ni(C4H13N3)2]2+ cation, together with two chloride anions and a water molecule for (I) and two nitrate anions for (II). The metal centre is coordinated to six nitrogens of the neutral dien ligands in a slightly distorted octahedral geometry. The two compounds have been characterised by FTIR and UV-Vis spectroscopy. Their morphology and size were studied by scanning electron microscopy (SEM). The thermal behaviour of the title compounds was also investigated. Calcination of the two complexes in air yielded Ni/NiO nanoparticles. The structures of both complexes were optimised and their simulated geometric parameters and vibrational modes were discussed and correlated with the experimental data. The antioxidant potential of both complexes was evaluated using DPPH, ferric reducing power tests and phosphomolybdenum assay.

Synthesis, structure, theoretical calculation and photocatalytic property of a novel Mn(II) supra-molecular compound containing SCN- and 2,2′-bipyridine ligands

A novel supra-molecular compound [Mn(SCN)2(byp)2] 1 (byp = 2,2′-bipyridine) was synthesized under hydrothermal conditions. Noteworthily, the SCN- in the title compound is derived from the in situ reaction of salicylaldehyde thiosemicarbazone. X-ray single-crystal diffraction analysis shows compound 1 is only a mononuclear structure, but it is expanded into a 3D supramolecular structure via H-bonds and π···π stacking. Hirshfeld Surface analysis shows C⋯H, H⋯H and S⋯H interaction are the main contribution of intermolecular interactions in the formation of compound 1. All of title compounds were characterized by IR spectroscopy, elemental analysis, XRD, XPS and TG analysis. The energy framework of compound 1 is dominated by dispersion interaction. The photocatalytic degradation ability of compound 1 for methylene blue is verified by photocatalytic degradation experiments (pH = 4: 44.6 %; pH = 7: 76.2 %; pH = 10: 78.8 %). Furthermore, the potential photocatalytic mechanism of compound 1 is inferred by UV–vis absorption spectra and Mott–Schottky curve.

Synthesis, Characterization and Energetic Properties of Hydroxymethyl-Bishomocubanone Derivatives.

The present work reports synthesis, characterization and theoretical insights on novel hydroxymethyl-bishomocubanone derivatives. Twelve new bishomocubanes (BHCs) were synthesized and fully characterized by various spectroscopic techniques and single crystal X-ray analysis. The densities of the title compounds were in the range of 1.30-1.59 g/cm3. Density-functional theory (DFT) based calculations at B3LYP/6-311++G(d,p) level of theory were performed on ten selected BHC based cage compounds. Propulsive and ballistic properties of newly synthesized hydroxymethyl-bishomocubanone derivatives in solid and liquid propulsion systems were calculated, and the results suggested that these compounds are superior to conventional fuel RP1 and binder HTPB. The detonation parameters revealed that these compounds are not explosive in nature and safe to use as solid propellants. Furthermore, kinetic and thermal stabilities of the title compounds were determined by HOMO-LUMO energy gap, ESP maps, impact sensitivity (h50) and bond dissociation energies (BDEs) followed by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Three compounds, a dinitroazide (Isp,vac=310.98 s), a dinitrate (Isp,vac=309.51 s), and a dinitronitrate (Isp,vac=309.20s) were found to be excellent candidates for volume limited applications.

Investigations on 5,6,7,8-tetrahydro-[1,2,4]triazolo[1,2-a]pyridazin-1-amines and related compounds: synthesis, chemical behaviour, structure elucidation and iNOS inhibitory activity.

The present work reports on the preparation of the hitherto unknown title compounds 5, with various synthetic routes described. The initially pursued concept of S-N exchange with varioius 1-substituted 3-methylsulfanyl-5,6,7,8-tetrahydro-1 H -[1,2,4]triazolo[1,2- a ]pyridazines 4 by using nitrogen nucleophiles was only marginally successful. The reactions proceeded slowly and the yields were low, mainly because of the pronounced formation of 5,6,7,8-tetrahydro-[1,2,4]triazolo[1,2- a ]pyridazin-1-imines 7 by oxidation of the heterocyclic amines 5 initially formed. The integration of the synthesis of 3-acylsulfanyl analogues with the more reactive leaving groups also failed. On the other hand, the cyclization of the hydrohalides of hexahydropyridazine-1-carboximidamide with aromatic aldehydes and some low molecular weight ketones gives significantly better results in the synthesis of the title compounds 5. The use of the hydrochloride 6b proved to be advantageous in comparison to the hydroiodide 6a because the yields were significantly better and the imines 7 formed at the same time only to a small extent. In addition, the starting compound 6b can be prepared in a single-step synthesis in very good yield from hexahydropyridazine hydrochloride 1 and cyanamide. The cyclization of N' -phenylhexahydropyridazine-1-carboximidamide hydrochloride 6c with substituted benzaldehydes gives the 3-aryl-substituted 2-phenyl-2,3,5,6,7,8-hexahydro -1H -[1,2,4]triazolo[1,2- a ] pyridazin-1-imines 8. In the context with the study of the reaction of hexahydropyridazine-1-carboximidamide hydroiodide 6a with cyclohexanone, the hexahydropyridazine-1-carboxamide 9 was specifically synthesized. This can be reacted with aromatic aldehydes to give the 5,6,7,8-tetrahydro-1 H -[1,2,4]triazolo[1,2- a ]pyridazin-1-ones 10 in very good yields. The results of the biological testing of representatives of the synthesized 5,6,7,8-tetrahydro-[1,2,4] triazolo[1,2-a]pyridazine-1-amines 5 show, in comparison to the already examined thions 3 and 3-methylsulfanyl derivatives 4, significantly less inducible nitric oxide synthase (iNOS) inhibitory activity.

Influence of the alkyl chain-length on the luminescent properties of 6‑hydroxy-2-naphthoate moieties: Preparation, crystal structure and Hirshfeld surface analysis

To further explore the luminescent materials, a set of 6‑hydroxyl-naphthoate derivatives have been obtained through the esterification reaction of 6‑hydroxy-2-naphthoic acid with a series of organic alcohols (methanol, ethanol, n-propanol and n-butanol, respectively) in the presence of phenyl sulfonic acid. The title compounds were characterized by FT-IR, elemental analysis (EA), UV–vis spectra, NMR and single-crystal X-ray diffraction. Compounds 1–5 are 6‑hydroxy-2-naphthoic acid, methyl 6‑hydroxy-2-naphthoate, ethyl 6‑hydroxy-2-naphthooate, n-propyl 6‑hydroxy-2-naphthoate and n‑butyl 6‑hydroxy-2-naphthoate, respectively. Compounds 1–5 crystallizes in the space group P21/c, Pna21, P21/n, P21/c and P-1, respectively. The C/OH···O hydrogen bonds can be observed. The luminescent emission maxima of compounds 1–5 can be found at 386, 393, 405, 407 and 420 nm in the solid state, respectively, indicating that the photoluminescent peaks occur the bathochromic-shift with the growth of the alkyl chain-lengths. Additionally, there exists the same order for the quantum yields. Meanwhile, the Hirshfeld surface analysis proves that the H···H interactions can be responsible for the emission maxima of these target compounds. The trend of the melting point decreases with the reduction of O···H interactions, and with the increment of the alkyl chain-lengths. The repulsion energy of the target compounds also shows the same tendency, which can be confirmed by the energy framework analysis.

Synthesis, anti-microbial, and docking studies of functionalized chromenyl phosphonates using ionic liquid catalyst.

Synthesis of functionalized chromenyl phosphonates by the reaction among 2-hydorxybenzaldehydes, dicyanoethane, and dialkyl phosphonates that was promoted by choline hydroxide ionic liquid catalyzes the simultaneous, Knoevenagel, Pinner, and phospha-Michael reactions, under neat condition at room temperature. Important phosphorus-containing compounds can be produced at a reasonable cost because of the mild reaction conditions and the inexpensive promoter choline hydroxide. Furthermore, the desired products can be obtained without the need for any extraction or chromatography steps. An alternate technique for the simple and high-yield synthesis of functionalized chromenyl phosphonates is offered by this protocol. The synthesized compounds were studied by anti-microbial activity and docking studies. The title compounds molecular docking investigations demonstrated their efficacy as therapeutic agents against DNA Gyrase B and Aspergillus niger endoglucanase in both antibacterial and antifungal inhibition, and they identified compounds 4a, 4d, 4l, 4p, and 4q as promising candidates for microbial treatment, with binding affinities ranging from -6.9 to -7.4kcal/mol.

Antimicrobial effects of new tetrahydrofurans

The increasing challenge of antimicrobial resistance (AMR) necessitates abrupt attention to discovering a new class of antimicrobials. In this study, we made efforts to prepare some fluoro-phenyl tetrahydrofurans-based DNA gyrase inhibitors as anti-microbial agents. To obtain the title compounds difluoro phenyl tetrahydrofurans (1-12), we used fluorophenyl-tetrahydrofuran and methyl benzenesulfonate to react with isoxazole derivatives and heterocyclic compounds bearing secondary amines in the presence of dimethylformamide (DMF) and sodium hydride (NaH) or potassium carbonate (K2CO3). The compounds were obtained in moderate to excellent yields and were characterized with FTIR, HRMS, NMR, etc. Among all compounds (1-12), compounds 1, 2, 11, and 12 were active against various Gram-positive and Gram-negative bacteria at a low concentration (MIC ranged between 1.25 and 9.75 μg/mL) and displayed low toxicity towards mammalian cells. We testified the in vitro DNA gyrase inhibitory potential for these compounds. A molecular docking study and an ADMET assessment study were carried out to understand the mode of interaction of ligand-DNA gyrase. In conclusion, we screened the compounds 1, 2, 11, and 12 for further clinical and pre-clinical studies.

Longifolene-Derived Primary Amine Carboxylates for Sustainable Weed Management: Synthesis and Herbicidal Activity.

Twelve novel longifolene-derived primary amine carboxylates were synthesized and evaluated for herbicidal activity. The structures of title compounds were confirmed by Fourier-transform infrared spectroscopy, 1H nuclear magnetic resonance (NMR), 13C NMR, and high-resolution mass spectrometry. The results showed that all the synthesized compounds exhibited higher herbicidal activity than the corresponding carboxylic acids involved in the reaction and the commercial herbicide glyphosate; some of them even possessed inhibition rates of 100% against Lolium multiflorum Lam. and Brassica campestris at low concentrations (0.039-0.313 mmol/L). Moreover, structural factors, including types of carboxylates and carbon chain length, had a great influence on the herbicidal performance. The herbicidal activity of dicarboxylates was similar to or much higher than that of corresponding monocarboxylates and glyphosate. Furthermore, compound 5l was found to be the most active candidate against the root and shoot growth of L. multiflorum Lam. and B. campestris with half maximal inhibitory concentrations (IC50) of around 0.010 and 0.023 mmol/L. The present work indicated that those prepared compounds have great potential to serve as high-performance botanical herbicides used at low doses.

Na2.64Mn1.64(MoO4)3 and Na2.62Ni1.69(MoO4)3: Physicochemical investigations and electrochemical properties as 3.5 V class positive electrode material for Na-batteries

Powders of two new mixed molybdates Na2.64Mn1.64(MoO4)3 (1) and Na2.62Ni1.69(MoO4)3 (2) have been prepared via a solid-solid reaction. They are isostructural, both crystallizing in monoclinic system (S. G.: C2/c), Z = 1, and the unit cell parameters a = 12.74109 (18) Å, b = 13.69390 (15) Å, c = 7.20028 (8) Å, β = 112.4314 (7) °, V = 1161.22 (2) Å3 (1), and a = 12.6368 (2) Å, b = 13.3633 (2) Å, c = 7.08501 (10) Å, β = 111.9248 (10) °, V = 1109.91 (3) Å3 (2). The structure consists of a 3D network of corners and edges sharing [MoO4] and [MO6] polyhedral, delimiting tunnels in which the Na ions partly site. The samples were investigated by powder X-ray diffraction, infrared spectroscopy, and scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy (SEM-EDX). The vibrational study confirms the existence of the MoO42− functional groups. Laser Raman spectroscopy showed that the MoO42− tetrahedra in the two compounds are more regular, suggesting high symmetry for the compound. The as-synthesized compounds are fiber-like grains with an average length of 10−1 μm. FT-IR spectra showed the presence of all the functional groups present in the compounds. Magnetisation measurements showed their paramagnetic behaviour. The title compounds were characterized by cyclic voltammetry (CV), electrochemical performance and limiting factors are also applied as electrode material for Na-ion batteries at room temperature. Benefiting from these advantages, between 1.5 V and 4.6 V, (1) and (2) deliver high specific capacities of 230 and 160 mA h g−1 after 60 cycles, and good rate performances, respectively. It can also be inferred that the prepared electrocatalyst showed for both phases excellent Hydrogen Evolution Reaction (HER) performance with an overpotential of 531 mV for Mn and 512 mV for Ni, required to afford a current density of 10 mA cm−2.

Synthesis of indole-functionalized isoniazid conjugates with potent antimycobacterial and antioxidant efficacy.

Aim: Developing potent medicinal alternates for tuberculosis (TB) is highly desirable due to the advent of drug-resistant lethal TB strains.Methods & results: Novel indole-isoniazid integrates have been synthesized with promising antimycobacterial action against the H37Rv strain, and the nitro analogs 4e and 4j show the highest efficacy with a minimum inhibitory concentration of 1.25μg/ml. The molecular docking studies against InhA support the experimental findings. Indole conjugates display remarkable radical quenching efficiency, and compounds 4e and 4j demonstrate maximum IC50 values of 50.19 and 52.45μg/ml, respectively. Pharmacokinetic analysis anticipated appreciable druggability for the title compounds.Conclusion: The notable bioaction of the indole-isoniazid templates projects them as potential lead in developing anti-TB medications with synergetic antioxidant action.

Aluminium in der Chemie der Frustrierten Lewis‐Paare

AbstractDieser Übersichtsartikel beschreibt die Entwicklung der Verwendung von Aluminiumverbindungen in der Chemie der frustrierten Lewis‐Paare (FLPs) in den letzten 14 Jahren. Es werden die Synthese, die Reaktivität und die katalytischen Anwendungen von intermolekularen, intramolekularen und sogenannten versteckten FLPs mit Phosphor‐, Stickstoff‐ und Kohlenstoff‐Lewis‐Basen erörtert. Die intrinsisch höhere Acidität von Aluminiumverbindungen im Vergleich zu ihren Bor‐Analoga eröffnet unterschiedliche Reaktionswege. Die Ergebnisse werden in einer mehr oder weniger chronologischen Reihenfolge präsentiert. Es wird gezeigt, dass Al‐FLPs mit einer Vielzahl von polaren und unpolaren Substraten reagieren und sowohl stabile Addukte bilden als auch reversibel Bindungen aktivieren. Folglich werden einige katalytische Anwendungen der Titelverbindungen vorgestellt, wie z. B. die Dimerisierung von Alkinen, die Hydrierung von tert‐butylethylen und Iminen, die Aktivierung von C−F‐Bindungen, die Reduktion von CO2, die Dehydrierung von Aminboran und der Transfer von Ammoniak. Darüber hinaus wurden verschiedene Al‐FLPs als Initiatoren in Polymerisationsreaktionen eingesetzt.

Aluminum in Frustrated Lewis Pair Chemistry.

This review article describes the development of the use of aluminum compounds in the chemistry of frustrated Lewis pairs (FLPs) over the last 14 years. It also discusses the synthesis, reactivity and catalytic applications of intermolecular, intramolecular and so-called hidden FLPs with phosphorus, nitrogen and carbon Lewis bases. The intrinsically higher acidity of aluminum compounds compared to their boron analogs opens up different reaction pathways. The results are presented in a more or less chronological order. It is shown that Al FLPs react with a variety of polar and non-polar substrates and form both stable adducts and reversibly activate bonds. Consequently, some catalytic applications of the title compounds were presented such as dimerization of alkynes, hydrogenation of tert-butyl ethylene and imines, C-F bond activation, reduction of CO2, dehydrogenation of amine borane and transfer of ammonia. In addition, various Al FLPs were used as initiators in polymerization reactions.

MTP−IL] as Mesoporous Heterogeneous Organocatalyst for the One‐Pot Synthesis of Indeno [1,2‐b] Quinoxalin‐11‐Ylidenamine Derivatives: A Green, Sustainable, and Metal‐Free Protocol

AbstractHerein, we report a green, sustainable, and metal‐free, one‐pot three‐component protocol for the synthesis of indeno [1, 2‐b] quinoxalin‐11‐ylidenamine derivatives using a novel, effective, and recyclable mesoporous heterogeneous organocatalyst [MTP−IL]. [MTP−IL] was constructed by immobilizing an imidazolium‐cation‐based ionic liquid on a melamine−terephthalaldehyde covalent organic polymer and was thoroughly characterized using several analytical techniques. It displayed high thermochemical stability and catalytic efficacy, offering title compounds with 90–94 % yields in a short reaction time, and was recyclable for up to six cycles. The synthesized compounds were characterized through FTIR, 1H, and 13C Nuclear Magnetic Resonance (NMR), and the molecular structure of N′‐(11H‐indeno[1,2‐b]quinoxalin‐11‐ylidene)benzohydrazide (7) was confirmed by the Single Crystal XRD (SCXRD) analysis. The key features of the present protocol are the use of ethanol as a green solvent, easy catalyst recovery, a simple work‐up procedure, and zero involvement of any metal.

Biocatalyst mediated green approach for 1,8-dioxo-octahydroxanthenes: SCXRD, Hirshfeld analysis and DFT studies as inhibitors of HIV reverse transcriptase

AIDS, caused by human immunodeficiency virus (HIV) is persistent on being one among the deadliest disease of all time. It destroys the immune system of the body and there is currently no effective cure for this. In this regard, in continuation to our studies on green catalysts, more efficient, constructive, and environmentally sustainable protocols for the synthesis of xanthene and its derivatives as HIV Reverse Transcriptase inhibitors were developed with the use of biocatalyst via baker's yeast that explores a viable approach on expanding environmental challenges and enlightens the superiority and exclusivity of this protocol. The current approach manifests numerous notable advantages that include ease of preparation, handling and benignity of the catalyst, low cost, green reaction conditions, facile workup, excellent yields (87–96 %) with extreme purity. The title compounds were docked on the crystal structure of a catalytic complex of HIV-1 reverse transcriptase (PDB: 1RTD). The C-score values achieved in the range 6.68–3.05 suggest that docking analysis was propitious signifying the review of all the forces of interaction between the ligand and the protein. The crystal studies and DFT analysis of compound 3d correlate the optimized geometrical features with empirically accessible XRD data.

Design, synthesis and biological Evaluation of novel chromones having 3,4-dihydropyrimidin-2(1H)-one core at C-8 in combination with triazoles: New α-glucosidase inhibitors and anti-bacterial agents

The Biginelli reaction synthesizes dihydropyrimidones through a multi-component reaction. A β-ketoester, aldehyde, and urea or thiourea react in the presence of an acid catalyst to form these dihydropyrimidones. 3,4-Dihydropyrimidin-2(1H)-One/Chromone/Triazole hybrids (9a-9l) were synthesized by multiple steps including one pot Biginelli multicomponent reaction depicted in the scheme. An efficient method for the Biginelli reaction of Chromone aldehyde, acetoacetate esters, and urea employed in the presence of ferric chloride is described. In the end, we have successfully synthesized twelve derivatives of 3,4-Dihydropyrimidin-2(1H)-One/Chromone/Triazole hybrids and subjected them to testing for Antibacterial activity and α-glucosidase inhibition activity. Among these derivatives, compound 9g (IC50 = 142.92 nmol) and 9e (144.49 nmol) exhibited significant inhibitory activity in comparison to the positive control acarbose (IC50 = 350.91 nmol). Compound 9g demonstrated the most significant suppression against Escherichia coli and Bacillus cereus, with zone diameters of 8.8 ± 1.35 mm and 9.1 ± 0.23 mm, respectively. Compound 9b displayed a clear area where bacterial growth was inhibited, measuring 7.5 ± 1.25 mm against Klebsiella pneumonia. Compound 9k exhibited a zone of inhibition measuring 8 ± 1.2 mm in radius against Staphylococcus epidermidis. The docking results for the synthesized compounds indicate that compound 9b exhibited the most favorable docking score of −10 kcal/mol, whereas compound 9a had the second-best docking score of −8.7 kcal/mol. Molecular docking was utilized to examine the interactions between the title compounds and α-glucosidase, in order to provide valuable insights. The data obtained revealed significant interactions that contribute to the inhibitory effects of the drugs against α-glucosidase. These compounds exhibit significant potential as attractive initial candidates for the development of new α-glucosidase inhibitors.

Design, synthesis, in vitro, and in silico anti-α-glucosidase assays of N-phenylacetamide-1,2,3-triazole-indole-2-carboxamide derivatives as new anti-diabetic agents

In this work, a novel series of N-phenylacetamide-1,2,3-triazole-indole-2-carboxamide derivatives 5a–n were designed by consideration of the potent α-glucosidase inhibitors containing indole and carboxamide-1,2,3-triazole-N-phenylacetamide moieties. These compounds were synthesized by click reaction and evaluated against yeast α-glucosidase. All the newly title compounds demonstrated superior potency when compared with acarbose as a standard inhibitor. Particularly, compound 5k possessed the best inhibitory activity against α-glucosidase with around a 28-fold improvement in the inhibition effect in comparison standard inhibitor. This compound showed a competitive type of inhibition in the kinetics. The molecular docking and dynamics demonstrated that compound 5k with a favorable binding energy well occupied the active site of α-glucosidase.

Golden ratio of the r+/r- for the structure-selectivity in the thermoelectric BaZn2-xCdxSb2 system

A total of five Zintl phase compounds in the solid-solution BaZn2-xCdxSb2 (0.10(2) ≤ x ≤ 2) system have been successfully synthesized by the molten Pb-flux method. Both powder X-ray and single-crystal X-ray diffraction analyses proved that the title compounds displayed the phase transition between the BaCu2S2-type phase (space group Pnma, Z = 4) and the CaAl2Si2-type phase (space group P3¯m1, Z = 1) depending on the Zn/Cd mixed ratio. Furthermore, this kind of structure selectivity was dictated by the radius ratio criterion between the cationic and the anionic elements (r+/r–): three Zn-rich compounds with the r+/r– > 1 (BaZn1.90(1)Cd0.10Sb2, BaZn1.75(2)Cd0.25Sb2, and BaZn1.62(2)Cd0.38Sb2) preferred to adopt the BaCu2S2-type phase, while two Cd-rich compounds with the r+/r– ≤ 1 (BaZn0.16(2)Cd1.84Sb2 and BaCd2Sb2) preferred to crystallize in the trigonal CaAl2Si2-type phase. A series of TB-LMTO calculations using the two hypothetical models: BaZn1.5Cd0.5Sb2 and BaZn0.5Cd1.5Sb2, proved that a resonance peak in the density of states of BaZn1.5Cd0.5Sb2 implied the enhanced Seebeck coefficient of the three Zn-rich compounds, and the reduction of band gap observed in a band structure of BaZn0.5Cd1.5Sb2 influenced the electrical conductivity of the Cd-rich BaZn0.16(2)Cd1.84Sb2. Temperature-dependent thermoelectric property measurements showed the maximum ZT of 0.54 for the quaternary BaZn1.62(2)Cd0.38Sb2, which should mainly be attributed to the reduced κtot due to the Zn and Cd disordering in the anionic frameworks.