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By following one-pot synthesis, an acridinediones derivative compound 3,3,6,6-tetramethyl-9-(4-methoxyphenyl)-10-(4-chlorophenyl)-1,8-dioxodecahydroacridine dimethyl sulfoxide, C30H32O3ClNS·C2H6OS has been synthesized using a green protocol and its crystal structure is determined by X-ray structure analysis. The crystals are Triclinic with space group P , Z = 2. The crystal structure was solved by direct method and refined by full matrix least squares procedure to a final R value of 0.0587 for 4137 observed reflections. The pyridine ring adopts flattened boat conformation whereas both cyclohexene adopts envelope conformations. The crystal structure is stabilized by C–H⋅⋅⋅O and C–H⋅⋅⋅π hydrogen bonds involving the DMSO solvent molecule which are further understood through Hirshfeld surface analysis. [ABSTRACT FROM AUTHOR]

The communication deals with the eco-friendly synthesis and X-ray crystal structure of an organic carbonitrile, namely 6-amino-3-phenyl-4-(pyridin-4-yl)-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile. The title compound was synthesized in 89% yield by following a simple, straightforward and highly efficient multicomponent one-pot protocol under the excellent catalytic influence of non-toxic trisodium citrate dihydrate under ambient conditions. X-ray diffraction studies reveal the packing of molecules in the crystal, which is strongly influenced by both intra and intermolecular hydrogen interactions. In addition, aromatic π–π interactions stabilize the molecular chains propagating along [001]. [ABSTRACT FROM AUTHOR]

In the present investigation, we report the synthesis and characterization of three novel nickel(II) [Ni(L)2] (1) and copper(II) [Cu(L)2] (2a) and [Cu(L)2] (2b) complexes, which are made through the coordination of (E)-1-(2-methoxybenzylidine)-4-phenylethiosemicarbazone (HL) as bidentate N,S-ligand. Several modern techniques including experimental electronic and fluorescence spectroscopy, single-crystal X-ray crystallography, molecular docking and BSA-binding are used to characterize the isolated coordination compounds. X-ray crystallography, FT-IR and UV–visible spectra agree with the observed crystal structures. The crystallographic and spectroscopic studies confirmed that these complexes display four-coordinate square-planar trans-[MN2S2] coordination geometry, whose central metal(II) atom lies on the center of symmetry. Complexes 1 and 2a crystallized in the orthorhombic system of the space group Pbca whereas 2b crystallized in the monoclinic system of P21/c. The binding affinity of complexes towards bovine serum albumin (BSA) was determined by UV–visible and fluorescence spectrophotometric methods. The cytotoxic/antiproliferative potential of the synthesized compounds on human cell lines was also investigated by MTT assay. [ABSTRACT FROM AUTHOR]

Ni (II) and Cu (II) complexes [Ni(L)2] (1) and [Cu(L)2].H2O (2) was synthesized using a Schiff base (HL) ligand which was formed by 5-bromosalicylaldehyde with 2-methoxybenzeneamine. The crystal structure of the ligand and its complexes were determined through crystal X-ray diffraction. The most plausible geometry for the 1:2 complexes appeared to be distorted octahedral. The TG-DTA analysis of complex (1) and (2) exhibits an exothermic peaks at around 367-393 °C. Their inhibition studies was performed on urease. Complex (1) and (2) can inhibit urease activity, with IC50 values of 2.10 ± 0.06 and 2.10 ± 0.10 µmol L−1, respectively. Their DFT study were also discussed. [ABSTRACT FROM AUTHOR]

A combined experimental and theoretical study is performed on DMSO solvated 7′-amino-1′,3′-dimethyl- 2,2′,4′-trioxo-1′,2′,3′,4′,4a′,8a′-tetrahydrospiro[indoline-3,5′-pyrano[2,3-d]pyrimidine]-6′-carbonitrile. The compound is studied by NMR, IR spectroscopy, and single crystal X-ray analysis. The crystal structure of the molecule is stabilized by intermolecular N-H…N, N-H…O, and C-H…π interactions. In the crystal, the molecules form hydrogen-bonded chains running along the b axis of the unit cell. In the present work, we have applied density functional theory (DFT) to explore the nonlinear properties of the molecule. The harmonic vibrational frequencies are calculated and compared with experimental FT-IR frequencies. The observed and calculated frequencies are found to be in good agreement. The calculated values of the HOMO-LUMO energy gap shows that a charge transfer occurs within the molecule. [ABSTRACT FROM AUTHOR]

We present a novel approach for designing new hard magnets by forming stacks of existing binary magnets to enhance the magneto crystalline anisotropy. This is followed by an attempt at reducing the amount of expensive metal in these stacks by replacing it with cheaper metal with similar ionic radius. This strategy is explored using examples of FePt, MnAl and MnGa. In this study a few promising materials are suggested as good candidates for hard magnets: stacked binary FePt2MnGa2 in structure where each magnetic layer is separated by two non-magnetic layers, FePtMnGa and FePtMnAl in hexagonally distorted Heusler structures and FePt0.5Ti0.5MnAl. [ABSTRACT FROM AUTHOR]

Recently, a new series of layered ternary compounds coming from pseudobinary RGaO 3 – R 2 Ti 2 O 7 have been synthesized and stabilized in out-of-equilibrium (quenching in air) conditions. One of them is the LuGa 1/3 Ti 2/3 O 3+x/2 (LGTO) compound forming a superstructure of Lu - O and Ga/Ti – O layers stacked along the c-axis. Accordingly, it is imperative to investigate the dielectric behavior in order to envision possible technological applications. Based on this compound, High-Entropy Ceramic (HECs) material has been designed introducing five equimolar rare earth elements in the Lu site with a chemical formula Lu 0.2 Yb 0.2 Tm 0.2 Er 0.2 Ho 0.2 Ga 1/3 Ti 1/3 O 3+x/2 (RGTO). The X-ray diffraction pattern shows that the single-phase was successfully formed and then sintering temperatures at 1300, 1400, and 1500 °C were performed to investigate the phase stability. SEM - EDX images show homogeneous cation distribution in both the LuGa 1/3 Ti 2/3 O 3+x/2 compound and the designed high-entropy ceramic material. A comparison of the band-gap energy estimated from the UV–vis spectra for the pristine and designed High-entropic compounds is reported. Finally, the dielectric properties were analyzed between room temperature up to 500 °C. It is found that the disorder induced by the multicomponent cations in the crystal lattice has no considerable effect on the dielectric constant and in the extrinsic (lattice defects) and intrinsic (charge compensations) dielectric loss tangent. It is argued that the very good dielectric constant (∼150 for LGTO and 21–13 for HECs – RGTO) and loss tangent (>0.01 in both compounds) over a wide range of temperatures along with moderately high values in the band-gap energy (∼3.71 eV for LGTO and ∼3.86 eV for RGTO) make this group of materials good candidates for capacitors and related devices. [Display omitted] • High-Entropy Ceramic material has been successfully designed by the solid-state method. • XRD patterns show a single phase in pristine and high-Entropic Ceramic samples. • The band-gap energy was obtained by UV–vis spectroscopy. • The dielectric constant and dielectric loss versus temperature was obtained. • The good dielectric values anticipate applications as capacitors and related devices. [ABSTRACT FROM AUTHOR]

2-Amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[3,2- c]pyran-3-carbonitrile, CHNO is synthesized via one-pot multi-component reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst. Its structure is determined by single-crystal X-ray diffraction technique The crystals are monoclinic, a = 10.7357(12), b = 8.7774(8), c = 15.0759(16) Å, β = 103.575(11)°, Z = 4, sp. gr. P2/ n, R = 0.0551 for 1696 observed reflections. The crystal structure is stabilized by N-H···N, C-H···O, and C-H···π interactions. [ABSTRACT FROM AUTHOR]

Two carbonitrile compounds, 2-amino-4-(3-nitrophenyl)-5-oxo-4,5-dihydropyrano[3,2- c] chromene-3-carbonitrile ( I) and 2-amino-7,7-dimethyl-4-(4-nitrophenyl)-5-oxo-5,6,7,8-tetrahydro-4 H-chromene-3-carbonitrile ( II), were synthesized, and their crystal structures were determined by X-ray diffraction technique. The crystals are triclinic, a = 7.7970(12), 8.2171(7), b = 9.0390(10), 9.2238(7), c = 15.148(2), 14.5585(11) Å, α = 81.439(10)°, 74.895(6)°, β = 75.194(12)°, 87.392(6)°, γ = 76.151(11)°, 78.552(7)°, for I and II, respectively, Z = 2, sp. gr. P $$\overline 1$$. The pyran ring in both the compounds deviates significantly from planarity and adopts boat conformation. The crystal structure is stabilized by N-H···O and N-H···N hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, 2-amino-5-oxo-4-phenyl-4,5-dihydropyrano[3,2- c]chromene-3-carbonitrile was synthesized in excellent yield by one-pot multicomponent reaction and its crystal structure is determined by X-ray structure analysis. The crystals are monoclinic, sp. gr. P2/ c, a = 9.0750(6), b = 13.2729(8), c = 12.6892(9) Å, β = 96.975(6)°, Z = 4; R = 0.0466 for 1771 observed reflections. The crystal structure is stabilized by N-H···N, N-H···O and C-H···O hydrogen bonds. In addition, C-H···π and π···π interactions are observed in the crystal structure. [ABSTRACT FROM AUTHOR]

The carbonitrile compound, 2-amino-5-oxo-4-propyl-4,5-dihydropyrano[3,2- c]chromene-3-carbonitrile was synthesized, in 83% yield, by one-pot multicomponent reaction of butyraldehyde, malononitrile and 4-hydroxycoumarin using 10 mol% urea as an organo-catalyst at room temperature, and its crystal structure was determined by X-ray diffraction technique. The crystals are triclinic, a = 7.7379(5), b = 8.7520(6), c = 11.6589(5) Å, α = 96.668(4)°, β = 100.033(4)°, γ = 112.547(6)°, Z = 2, sp. gr. P. Both pyran rings in the molecule adopt a boat conformation. The crystal structure is stabilized by N-H···O and N-H···N hydrogen bonds. [ABSTRACT FROM AUTHOR]

A 1D coordination polymer [Nd(INA)(HO)] ( I) and a dimeric complex with mononuclear asymmetric unit [Nd(NA)(HO)] ( II) (HINA = isonicotinic acid and HNA = nicotinic acid) were synthesized. The compounds were characterized by elemental analyses, infrared spectroscopy and single crystal X-ray diffraction studies (CIF file CCDC nos. 938976 ( I) and 939061 ( II). X-ray crystal structure analysis reveals that both compounds exhibit rich structural chemistry. Compounds I and II belong to the monoclinic system with space group P2/ c. Thermogravimetric analysis has been performed to investigate their thermal stability. The coordination polymer I has meso-porous structure with average diameter of pores (∼4 nm) and BET surface area 13.62 m/g. [ABSTRACT FROM AUTHOR]

The present work consists of synthesis, structural characterization, spectral, density functional theory (DFT), antimicrobial, and anticancer studies of two copper(II) complexes, [Cu(THEEN)(DNB)](DNB) (1) and [Cu(TEAH3)2](DNB)2(2). In these complexes, THEEN is N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine, a tetrapodal ligand, and TEAH3is tris(2-hydroxyethyl)amine, a tripodal ligand, and the counter-anion is 3,5-dinitrobenzoate (DNB−). X-ray crystallography studies reveal that both complexes have distorted octahedron geometries. DFT studies have been performed to calculate structural parameters, vibrational bands, and energy gaps of frontier orbital (HOMO-LUMO) with B3LYP/6–31G*/LANL2DZ level of theory using DMSO as solvent. The theoretical and crystallographic analyses are consistent. Antimicrobial studies have been performed with new copper(II) complexes against Gram(+) bacteria (Staphylococcus aureus), Gram(−) bacteria (Serratia marcescens,Sphingobium japonicum,andStenotrophomonas maltophilia) and fungal species (Candida albicans,Aspergillus niger,andSaccharomyces cerevisiae). The copper(II) complexes have also shownin vitrocytotoxicity on MCF-7, HCT-116, and HL-60 human cell lines. This study demonstrates that2was active against MCF-7 cell lines with IC50of 23 μg/mL. The present work consists of synthesis, crystal structure, DFT studies, antimicrobial, and anticancer activities of [Cu(THEEN)(DNB)](DNB) (1) and [Cu(TEAH3)2](DNB)2(2). Both complexes have distorted octahedron geometries with Jahn–Teller distortion. The theoretical and crystallographic analyses are consistent with each other. [ABSTRACT FROM AUTHOR]

Phosphopantetheine adenylyltransferase (PPAT, EC. 2.7.7.3) catalyzes an essential step in the reaction that transfers an adenylyl group from adenosine tri phosphate (ATP) to 4′-phosphopantetheine (pPant) yielding 3′- dephospho-coenzyme A (dPCoA) and pyrophosphate (PP) in the coenzyme A (CoA) biosynthesis pathway. The enzyme PPAT from Acinetobacter baumannii (Ab PPAT) was cloned, expressed and purified. The binding studies of Ab PPAT were carried out with two compounds, tri‑sodium citrate (TSC) and l -ascorbic acid (LAA, vitamin-C) using fluorescence spectroscopic (FS) and surface Plasmon resonance (SPR) methods. Both methods provided similar values of dissociation constants for TSC and LAA which were of the order of 10−8 M and 10−5 M respectively. The computer aided docking studies indicated fewer interactions of LAA with Ab PPAT as compared to those of TSC. The freshly purified samples of Ab PPAT were crystallized. The crystals of Ab PPAT were soaked in the solutions containing TSC and LAA. However, the crystals of the complex of Ab PPAT with LAA did not diffract well and hence the structure of the complex of Ab PPAT with LAA could not be determined. On the other hand, the crystals of the complex of Ab PPAT with TSC diffracted well and the structure was determined at 1.76 Å resolution. It showed that TSC bound to Ab PPAT at the ATP binding site and formed several intermolecular contacts including 12 hydrogen bonds. The results of binding studies for both TSC and LAA and the structure of the complex of Ab PPAT with TSC clearly indicated a potential role of TSC and LAA as antibacterial agents. • Ascorbic acid and Citric acid bind to Ab PPAT with high affinities. • Structure of Ab PPAT with citric acid was determined at 1.76 Å resolution. • Structure of Ab PPAT with citric acid shows that it binds at substrate binding site. • Both compounds show antibacterial effects against sensitive and resistant isolate. [ABSTRACT FROM AUTHOR]

In the present work, we have developed a novel, ecofriendly method for the synthesis of ZnO superstructures for the first time through the thermal decomposition of zinc nitrate precursor without using any fuel. The synthesized materials were thoroughly characterized using various analytical tools such as X-ray diffraction, Fourier-transform infrared spectrometry, UV-vis, scanning electron microscopy, and transmission electron microscopy. Further, it has been used as a photocatalyst for the degradation of one of the environmental pollutants such as methylene blue and also as a biosensor toward the detection of dopamine at trace level. The as-synthesized ZnO nanoparticles showed superior catalytic activity toward the degradation of methylene blue dye with high degree of recyclability with yellow light emitting photoluminescence. The developed sensor showed a linear range for dopamine up to 300 μM with a detection limit of 1 μM with reproduced results over periods of several months without any deviation in its electrochemical performance. [ABSTRACT FROM AUTHOR]