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ABSTRACT Chemical investigation of the Liuweizhiji Gegen‐Sangshen oral liquid afforded one new diphenyl ether derivative (1), together with one known compound (2). Their structures were established by 1D and 2D NMR, and HR‐ESI‐MS spectroscopic analysis and the absolute configuration of 1 was confirmed by ECD calculation. Compounds 1 and 2 were evaluated for the cytotoxic activities, and compounds 1 and 2 showed weak cytotoxic activities towards HepG2 human liver cancer cells, with IC50 values of 97.3 and 79.6 μM, respectively. [ABSTRACT FROM AUTHOR]

A new series of 6‐methoxy‐2‐naphthalene based pyrimidinones were synthesized via one pot‐three component synthetic reaction of aryl aldehydes, 6‐methoxy‐2‐acetonapthone and urea in the presence of nano zinc ferrite catalyst under conventional method. The synthesized compounds were characterized by their spectral techniques including FT‐IR, H1, C13 NMR, LCMS, and analysis of elements. Molecular docking analysis was also performed to identify the protein‐ligand interactions and binding energy of synthesized compounds. Biological studies of all synthesized pyrimidinone compounds have been measured against bacterial and fungal strains by calculating the zone of inhibition. [ABSTRACT FROM AUTHOR]

The structure and 1H NMR chemical shifts of a new structural analogue of endogenous thyronamines, 4-[4-(2-aminoethoxy)benzyl]aniline, have been simulated in the framework of the density functional theory. The molecular geometry of the title compound has been optimized at the B3LYP level of theory using 6-31G(d,p), 6-31+G(d,p), and 6-311G(d,p) basis sets both for the isolated molecule and including solvent effect. The 1H NMR chemical shifts of 4-[4-(2-aminoethoxy)benzyl]aniline have been estimated on the basis of magnetic shielding constants calculated by the GIAO method. In the calculations of both optimal molecular geometry and magnetic shielding constants, nonspecific solvation with dimethyl sulfoxide and methanol was considered in terms of the polarizable continuum model (IEFPCM). Linear correlations have been found between the theoretical and experimental chemical shifts of 4-[4-(2-aminoethoxy)benzyl]aniline in methanol-d4 and DMSO-d6. [ABSTRACT FROM AUTHOR]

The title compound and its hydroxymethyl precursor have been fully characterised for the first time. The IR spectra, fully assigned 1H and 13C NMR spectra, and X-ray structures are presented for both compounds. Both compounds form hydrogen-bonded dimers in the crystal structures. [ABSTRACT FROM AUTHOR]

Phycocyanin (PC) is a naturally occurring green pigment in Spirulina. It was extracted by ultrasonic extraction using green technology, and its structure was studied using IR- and NMR-spectroscopy. Spectral data confirmed the PC structure. This study also involves an in silico assessment of the diverse applications of green pigment PC. Utilizing QSAR, PreADME/T, SwissADME, and Pro-Tox, this study explores the safety profile, pharmacokinetics, and potential targets of PC. QSAR analysis reveals a favorable safety profile, with the parent structure and most metabolites showing no binding to DNA or proteins. PreADME/T indicates low skin permeability, excellent intestinal absorption, and medium permeability, supporting oral administration. Distribution analysis suggests moderate plasma protein binding and cautious blood–brain barrier permeability, guiding formulation strategies. Metabolism assessments highlight interactions with key cytochrome P450 enzymes, influencing drug interactions. Target prediction analysis unveils potential targets, suggesting diverse therapeutic effects, including cardiovascular benefits, anti-inflammatory activities, neuroprotection, and immune modulation. Based on the in silico analysis, PC holds promise for various applications due to its safety, bioavailability, and potential therapeutic benefits. Experimental validation is crucial to elucidate precise molecular mechanisms, ensuring safe and effective utilization in therapeutic and dietary contexts. DFT calculations, including geometry optimization, MEP analysis, HOMO-LUMO energy surface, and quantum reactivity parameters of the PC compound, were obtained using the B3LYP/6–311G(d,p) level. This integrated approach contributes to a comprehensive understanding of PC's pharmacological profile and informs future research directions. [ABSTRACT FROM AUTHOR]

Three new monosulfated polyhydroxysteroid glycosides, spiculiferosides A (1), B (2), and C (3), along with new related unsulfated monoglycoside, spiculiferoside D (4), were isolated from an ethanolic extract of the starfish Henricia leviuscula spiculifera collected in the Sea of Okhotsk. Compounds 1–3 contain two carbohydrate moieties, one of which is attached to C-3 of the steroid tetracyclic core, whereas another is located at C-24 of the side chain of aglycon. Two glycosides (2, 3) are biosides, and one glycoside (1), unlike them, includes three monosaccharide residues. Such type triosides are a rare group of polar steroids of sea stars. In addition, the 5-substituted 3-OSO3-α-L-Araf unit was found in steroid glycosides from starfish for the first time. Cell viability analysis showed that 1–3 (at concentrations up to 100 μM) had negligible cytotoxicity against human embryonic kidney HEK293, melanoma SK-MEL-28, breast cancer MDA-MB-231, and colorectal carcinoma HCT 116 cells. These compounds significantly inhibited proliferation and colony formation in HCT 116 cells at non-toxic concentrations, with compound 3 having the greatest effect. Compound 3 exerted anti-proliferative effects on HCT 116 cells through the induction of dose-dependent cell cycle arrest at the G2/M phase, regulation of expression of cell cycle proteins CDK2, CDK4, cyclin D1, p21, and inhibition of phosphorylation of protein kinases c-Raf, MEK1/2, ERK1/2 of the MAPK/ERK1/2 pathway. [ABSTRACT FROM AUTHOR]

A simplified synthesis of the title compound is reported and its 1H and 13C NMR data are fully assigned including determination of H–H and C–H coupling constants. Its X-ray structure has been determined for the first time. NMR data are also presented for the oxygen analogue. [ABSTRACT FROM AUTHOR]

The title compound and its hydroxymethyl precursor have been fully characterised for the first time. The IR spectra, fully assigned 1H and 13C NMR spectra, and X-ray structures are presented for both compounds. Both compounds form hydrogen-bonded dimers in the crystal structures.

Gerty T. and Carl F. Cori discovered, during research on the metabolism of sugars in organisms, the important role of the phosphate ester of a simple sugar. Glucose molecules are released from glycogen—the glucose stored in the liver—in the presence of phosphates and enter the blood as α-D-glucose-1-phosphate (Glc-1PH2). Currently, the crystal structure of three phosphates, Glc-1PNa2·3.5·H2O, Glc-1PK2·2H2O, and Glc-1PHK, is known. Research has shown that reactions of Glc-1PH2 with carbonates produce new complexes with ammonium ions [Glc-1P(NH4)2·3H2O] and mixed complexes: potassium–sodium and ammonium–sodium [Glc-1P(X)1.5Na0.5·4H2O; X = K or NH4]. The crystallization of dicationic complexes has been carried out in aqueous systems containing equimolar amounts of cations (1:1; X–Na). It was found that the first fractions of crystalline complexes always had cations in the ratio 3/2:1/2. The second batch of crystals obtained from the remaining mother liquid consisted either of the previously studied Na+, K+ or NH4+ complexes, or it was a new sodium hydrate—Glc-1PNa2·5·H2O. The isolated ammonium–potassium complex shows an isomorphic cation substitution and a completely unique composition: Glc-1PH(NH4)xK1−x (x = 0.67). The Glc-1P2− ligand has chelating fragments and/or bridging atoms, and complexes containing one type of cation show different modes of coordinating oxygen atoms with cations. However, in the case of the potassium–sodium and ammonium–sodium structures, high structural similarities are observed. The 1D and 2D NMR spectra showed that the conformation of Glc-1P2− is rigid in solution as in the solid state, where only rotations of the phosphate group around the C-O-P bonds are observed. [ABSTRACT FROM AUTHOR]

Potentially biologically active functionally substituted thiadiazolopyrimidines were obtained via three-component condensation of 5-amino-1,3,4-thiadiazole-2-thiol with aromatic aldehydes and CH-acids (acetoacetic ester and malononitrile). Probable mechanisms for the formation of products are suggested. Quantum-chemical calculation of the aminating reagent molecule 5-amino-1,3,4-thiadiazole-2-thiol showed the preference of the amino group as the most active nucleophilic center. The study of molecular docking shows the potential for binding one of the representatives of the thiadizolopyrimidine series and cytidine deaminase. The structure of the new compounds was established using IR and 1H NMR spectroscopies. [ABSTRACT FROM AUTHOR]

The results of previously published studies of the ion mobility, phase transitions, and electrophysical properties of tetrafluoroantimonates(iii) with heteroatomic cation sublattices composed of alkali metal and ammonium cations are analyzed, corrected, supplemented, and summarized. The influence of outer-sphere monovalent cations of different nature on the character of ion mobility, phase transitions, and conductivity in crystalline tetrafluoroantimonates(iii) is considered. It was found that phase transitions of most compounds in question are followed by the formation of superionic β-phases with a high conductivity of the order of 10−4–10−2 S cm−1 in the temperature range of 400–500 K. [ABSTRACT FROM AUTHOR]

NMRium is the first web-based software that allows displaying, processing, interpretation, and teaching of 1D and 2D NMR data in a user-friendly interface. It can import the most common data formats (e.g., JCAMP-DX, Bruker, Varian, and Jeol). While the scope for the use of NMRium encompasses a variety of applications such as being a component in data repositories or electronic lab notebooks (ELN), performing structure elucidation or preparing raw spectral data for publication, it also excels in enhancing teaching of NMR interpretation. In this paper, we present some current possibilities of this new tool. Several series of exercises are already provided on https://www.nmrium.org/teaching.

In this study, the geometric structure determination of 3,3'-(2-Methoxybenzylidene)bis(4-hydroxycoumarin) molecule and its parameters (bond length and angles), Nuclear Magnetic Resonance (NMR) spectroscopes, electrical (HOMO, HOMO-1, LUMO and LUMO+1) properties, Mulliken, NBO and Atomic Polar Tensor (APT) charges and Molecular Electrostatic Potential (MEP) surfaces have been theoretically calculated utilizing the Gaussian 09 software. All theoretical calculations were calculated by using B3LYP (Becke's 3-parameter hybrid functional using B exchange and LYP correlation) and HSEH1PBE (The exchange part of the screened Coulomb potential of Heyd, Scuseria, and Ernzerhof) levels of Density Functional Theory (DFT) method with 6-311++G(d,p) basis set. Moreover, DNA interactions have been viewed employing the molecular docking method of 3,3'-(2-Methoxybenzylidene) bis(4-hydroxycoumarin) molecule with the COVID-19 main protease (PDB 6LU7) responsible for the replication of corona virus. [ABSTRACT FROM AUTHOR]

The 3,6-difluoro derivative of ortho-carborane 3,6-F2-1,2-C2B10H10 was obtained by a triple sequence of deboronation and BF-insertion reactions. 3-Fluoro and, especially, 3,6-difluoro derivatives of ortho-carborane were found to have an increased propensity to deboronation with elimination of the BF group under the action of even weak nucleophilic agents, which, apparently, is explained by a reduced electron density on the boron atoms bearing fluorine atoms. The 6,6′-difluoro derivative of cobalt bis(dicarbollide) [6,6′-F2-3,3′-Co(1,2-C2B9H10)2]− was obtained from 3-fluoro-nido-carborane [3-F-7,8-C2B9H11]−. The new fluoro derivatives of ortho-carborane were characterized by multinuclear NMR spectroscopy. [ABSTRACT FROM AUTHOR]

This document is a compilation of various research articles on the synthesis and potential applications of Schiff bases. Schiff bases are organic compounds that have shown promise as antimicrobial agents, anticancer drugs, antimalarial agents, and antioxidants. The articles discuss the synthesis, characterization, and biological activities of Schiff bases and their metal complexes. They also explore the structure-activity relationship and mechanism of action of these compounds. The research presented in these articles provides valuable insights for the development of new therapeutic agents. [Extracted from the article]

The 3,6-difluoro derivative of ortho-carborane 3,6-F2-1,2-C2B10H10 was obtained by a triple sequence of deboronation and BF-insertion reactions. 3-Fluoro and, especially, 3,6-difluoro derivatives of ortho-carborane were found to have an increased propensity to deboronation with elimination of the BF group under the action of even weak nucleophilic agents, which, apparently, is explained by a reduced electron density on the boron atoms bearing fluorine atoms. The 6,6′-difluoro derivative of cobalt bis(dicarbollide) [6,6′-F2-3,3′-Co(1,2-C2B9H10)2]− was obtained from 3-fluoro-nido-carborane [3-F-7,8-C2B9H11]−. The new fluoro derivatives of ortho-carborane were characterized by multinuclear NMR spectroscopy. [ABSTRACT FROM AUTHOR]

A simplified synthesis of the title compound is reported and its 1H and 13C NMR data are fully assigned including determination of H–H and C–H coupling constants. Its X-ray structure has been determined for the first time. NMR data are also presented for the oxygen analogue.

Three new monosulfated polyhydroxysteroid glycosides, spiculiferosides A (1), B (2), and C (3), along with new related unsulfated monoglycoside, spiculiferoside D (4), were isolated from an ethanolic extract of the starfish Henricia leviuscula spiculifera collected in the Sea of Okhotsk. Compounds 1–3 contain two carbohydrate moieties, one of which is attached to C-3 of the steroid tetracyclic core, whereas another is located at C-24 of the side chain of aglycon. Two glycosides (2, 3) are biosides, and one glycoside (1), unlike them, includes three monosaccharide residues. Such type triosides are a rare group of polar steroids of sea stars. In addition, the 5-substituted 3-OSO3-α-L-Araf unit was found in steroid glycosides from starfish for the first time. Cell viability analysis showed that 1–3 (at concentrations up to 100 μM) had negligible cytotoxicity against human embryonic kidney HEK293, melanoma SK-MEL-28, breast cancer MDA-MB-231, and colorectal carcinoma HCT 116 cells. These compounds significantly inhibited proliferation and colony formation in HCT 116 cells at non-toxic concentrations, with compound 3 having the greatest effect. Compound 3 exerted anti-proliferative effects on HCT 116 cells through the induction of dose-dependent cell cycle arrest at the G2/M phase, regulation of expression of cell cycle proteins CDK2, CDK4, cyclin D1, p21, and inhibition of phosphorylation of protein kinases c-Raf, MEK1/2, ERK1/2 of the MAPK/ERK1/2 pathway.

Fourier Transform infrared spectra (4000–400 cm−1) and Fourier Transform Raman spectra (4000–50 cm−1) were recorded for 2-chloro-4-phenylphenol (CP); 2-nitro-4-phenylphenol (NP); and 2-amino-4-phenylphenol (AP). 1H and 13C NMR spectra, along with UV-Vis spectra of the three samples were also measured. Quantum chemical calculations, at the level of DFT/B3LYP/6-311++G(d,p) theory were implemented to study their ground state geometry, vibrational wave numbers, infrared and Raman intensities, 1H and 13C NMR spectra, frontier molecular orbital parameters, NLO behavior, NBO properties, thermodynamic quantities, rotational constants and MESP behavior. TD-DFT variant was employed to simulate electronic transitions of these molecules. Observed and calculated vibrational frequencies agreed with an rms error 7.44, 8.98 and 6.97 cm−1, the corresponding RMSD values being 7.09, 9.39 and 6.59 cm−1 for CP, NP and AP, respectively. Experimental chemical shifts concurred, with their theoretical counterparts, with RMSD value, 0.19, 0.29 and 0.56 ppm for 1H NMR; and 6.34, 6.28 and 5.39 ppm for 13C NMR, respectively, in CP, NP and AP. This kind of agreement was also true for absorption maxima (λmax) of their electronic transitions in solution form. Frontier molecular orbitals were found useful to understand origin of electronic transition maxima and chemical reactivity of the three molecules which was supported by NBO analyses. The computations showed that the three molecules were potentially good for developing NLO materials. MESP investigations showed that the most reactive sites are at oxygen atoms in the three molecules. Moreover, we also made an attempt to understand the effect of deactivating (Cl, NO2) and activating (NH2) groups on certain properties of the three molecules. Presence of intra-molecular hydrogen bond was predicted in CP, NP and AP. Structure parameters for CP, NP and AP agree well with their experimental counterparts. Computed and measured frequencies, chemical shifts and electronic transitions agree acceptably. Effect of activating and deactivating groups is studied. CP, NP and AP are potential NLO materials. Intra-molecular charge transfer (ICT) is demonstrated using NBO analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] The equilibrium molecular structure of the 3,3-penta-methylenediaziridine (PMDA) molecule in the gas phase was determined by gas-phase electron diffraction in combination with quantum chemical calculations up to the CCSD(T)-AE/cc-pwCVQZ level and estimation of the mean amplitudes and anharmonic vibrational corrections using quadratic and cubic force fields. 1D and 2D 1H and 13C NMR spectra of PMDA in a CDCl 3 solution recorded at different temperatures revealed the temperature dependence of the chemical shifts of NH protons. Nonempirical simulations of small PMDA clusters, carried out at the DFT-B3LYP/6-31++G(2d,p) level, enabled us to suggest an interpretation of the NMR data [ABSTRACT FROM AUTHOR]

Two hydroxy-containing amidine derivatives have been synthesized by condensation of amino-alcohols such as monoethanolamine (MEA) and tris(hydroxymethyl)aminomethane (TRIS) with N,N-dimethylformamide dimethyl acetal. Their interaction with carbon dioxide, leading to the formation of polymeric ionic liquids, was studied by FTIR and NMR spectroscopy. Dilute solutions of polymeric ionic liquids are also investigated by measuring the relative viscosity during the reaction. It has been found that during interaction of MEA-based amidine with CO2 within first 60 min of reaction the intensities ratio of absorbance bands at 1644 and 1705 cm−1 dropped from 2.84 to 1.33. The linear relationship between the time of reaction and the mentioned ratio of intensities has been established. In the similar manner the changes in the intensities ratio of absorbance bands at 1696 and 1629 cm−1 can be used for monitoring the reaction between TRIS-based amidine and CO2. Solution of polymeric ionic liquid prepared by reaction of TRIS-based amidine with CO2 in i-propanol has been used for measuring molecular weight (Mw = 637, Mn= 349; Mw/Mn = 1.828) by gel-permeation chromatography.

In this work, the interaction of diarylmethylidene piperidones with acetylacetone and acetoacetic ester has been studied. It has been shown that the transition to piperidone in the basis of dienone does not allow the selective synthesis of products. It has been found that the direction of the reaction with 1,3-C,C-dinucleophilic reagents is infl uenced by the nature of peripheral ylidene substituents, which allows targeted synthesis of O-heterocyclization products (hexahydropyranopyridines) by introducing an NO2 group into the arylmethylidene fragment. Previously unknown substituted deca(octa)hydro(xanthenes)cyclopentachromenes have been synthesized. It has been established that the interaction of diarylmethylidenecyclanones with cyclohexa(penta)ne under conditions of mild basic catalysis (piperidine) proceeds nonselectively, the size of the cycle in the base of the initial substrate plays an important role, and the reaction products are always a mixture of substances (two or more). Based on the experimental data obtained, a scheme has been proposed for the formation of hydroxanthene and hydrocyclopentachromene fragments of the resulting products. It has been found that, while maintaining the general direction of the reaction, the determining role in the structure of the products is played by the size of the cycle (С5 ,С6 ) in the basis of the initial substrates. Six-membered fused fragments promote enolization and intramolecular O-heterocyclization of 1,5-diketone with the formation of polycyclic systems. The composition and structure of the synthesized compounds have been confi rmed by elemental analysis, IR and one-dimensional, two-dimensional NMR spectroscopy.

Biologically active Schiff bases namely (3,4-bis((E)-(arylidene)amino) phenyl)(phenyl)methanones have been synthesized through ultrasonicated condensation of (3,4-diaminophenyl)(phenyl)methanone and various benzaldehydes in ethanol medium. Synthesised Schiff bases have been examined by different techniques like molecular formula calculation, molecular weight determination, melting point determination, micro analysis and spectroscopic data. The in vitro antibacterial actions of these E-imines have been assessed against bacterial strains by zone inhibition and serial dilution methods. Further, molecular docking analysis of all E-imines have been accomplished to comprehend the order of binding of Schiff bases with protein. [ABSTRACT FROM AUTHOR]

X-ray crystallography has been used to characterise the title compound for the first time, 1H NMR, 13C NMR and IR spectroscopic data has also been updated from earlier reports. [ABSTRACT FROM AUTHOR]

Oxynitride glasses in Si-Al-O-N system were synthesized to investigate atomic arrangements in those glasses. Aerogels of silica (SiO2) and silica-alumina (SiO2-Al2O3) system were fabricated by drying wet gels in supercritical CO2 condition. The SiO2 gels were prepared from the silicon alkoxide with CH3 groups and the SiO2-Al2O3 gels were prepared from silicone and aluminum alkoxides. Ammonolysis were performed at TN = 750–1400 °C to synthesize oxynitride glasses. The nitrogen concentration in the resultant glasses increased with the increase in the ammonolysis temperatures and exceeded 34 eq.% by ammonolysis at 1300 °C. The specific surface area of these aerogels has been 1941 and 1159 m2 g−1, respectively. The glass structures were investigated by adopting 29Si and 27Al NMR measurements. In silicon oxynitride glasses, it was revealed that only one N atom occupies the nearest neighbor site around Si after ammonolysis at TN < 1200 °C, while two or more N atoms occupy the nearest neighbor site around Si after ammonolysis at TN > 1300 °C. In Si-Al-O-N glasses, the number of N atoms at around neighboring to Si atom varied with ammonolysis temperature but any traces of Al-N bonds were not found, indicating the bridging N in the form of Si-N-Al was absent in the glasses. Highlights: Silicon-based oxynitride glasses were prepared from aerogels via ammonolysis at high temperature. Nitrogen contents of the oxynitride glasses reached to higher than 34 eq.%. The local structures of the oxynitride glasses were investigated by 29Si and 27Al NMR measurements. It was found that most of inserted nitrogen was bonded to Si atoms. [ABSTRACT FROM AUTHOR]

Three isomorphous 0-D hybrid salts, namely, 2-methylimidazo[1,5-a]pyridinium trichloridoiodidozincate(II), (C8H9N2)2[ZnCl3.19I0.81] or [L]2[ZnCl3.19I0.81], (I), 2-methylimidazo[1,5-a]pyridinium dibromidodichloridocadmate(II), (C8H9N2)2[CdBr2.42Cl1.58] or [L]2[CdBr2.42Cl1.58], (II), and 2-methylimidazo[1,5-a]pyridinium trichloridoiodidocadmate(II), (C8H9N2)2[CdCl3.90I0.10] or [L]2[CdCl3.90I0.10], (III), are assembled from discrete 2-methylimidazo[1,5-a]pyridinium cations, L+, and mixed-halide tetrahalometallate anions. In the three structures, there are two crystallographically non-equivalent cations that were modelled as being rotationally disordered by 180°. In the lattices of the three compounds, a disordered state exists involving partial substitution of Cl by I for sites 2–4 in (I), Br by Cl for all four sites in (II) and Cl by I for site 2 in (III). In the solid state, the organic and inorganic sheets alternate parallel to the bc plane in a pseudo-layered arrangement. In the organic layer, pairs of centrosymmetically related trans-oriented cations form π-bonded chains. The adjacent tetrahalometallate anions in the inorganic layer show no connectivity with the shortest M...M separations being greater than 7 Å. A variety of C—H...X—M (X = Cl, Br, I) contacts between the organic and inorganic counterparts provide additional structural stabilization. The title structures are isomorphous with the previously reported structures of the chloride analogues, [L]2[ZnCl4] and [L]2[CdCl4].

X-ray crystallography has been used to characterise the title compound for the first time, 1H NMR, 13C NMR and IR spectroscopic data has also been updated from earlier reports.

Bulk glasses of the series (100−x)[0.4Na2O-0.2Nb2O5-0.4P2O5]-xB2O3 with x = 0–48 mol% B2O3 were prepared by slow cooling in air. Their glass transition temperature increases within the range of 0–16 mol% B2O3, but further additions of B2O3 result in its decrease. Their structure was investigated by Raman, 11B, and 31P MAS NMR spectroscopy. The relative number of BO4 units decreases with increasing B2O3 content, while the number of BO3 units increases up to 59 % at x = 48. The upfield shift of a broad resonance peak in the 31P MAS NMR spectra is ascribed to an increasing connectedness of the structural network with increasing B2O3 content. Strong Raman band at 916–929 cm−1 shows on the presence of NbO6 octahedra in the structural network of these glasses. With the B2O3 addition, a decrease in DC conductivity is observed, which is attributed to the decrease in the concentration of Na+ ions. [ABSTRACT FROM AUTHOR]

We have successfully developed a new Mo-Al2O3/p-TSA organocatalyst which has improved the yield of the Mannich reaction. This protocol has the advantage of mild conditions, high yield, easy work-up, environmentally friendly procedure, and the solid catalyst was recycled. The catalyst was analysed by XRD, SEM, and EDS techniques. The synthesized Mo-Al2O3composites were used in the presence of p-toluene sulfonic acid (p-TSA) conducts the one-pot three-component Mannich reaction and various β-amino ketones prepared with good yields and characterized by IR, ¹H, and 13C NMR Techniques. [ABSTRACT FROM AUTHOR]

Three new ceramides (1–3) and three new cerebrosides (4, 8, and 9), along with three previously known cerebrosides (ophidiocerebrosides C (5), D (6), and CE-3-2 (7)), were isolated from a deep-sea starfish species, the orange cookie starfish Ceramaster patagonicus. The structures of 1−4, 8, and 9 were determined by the NMR and ESIMS techniques and also through chemical transformations. Ceramides 1–3 contain iso-C21 or C23 Δ9-phytosphingosine as a long-chain base and have C16 or C17 (2R)-2-hydroxy-fatty acids of the normal type. Cerebroside 4 contains C22 Δ9-sphingosine anteiso-type as a long-chain base and (2R)-2-hydroxyheptadecanoic acid of the normal type, while compounds 8 and 9 contain saturated C-17 phytosphingosine anteiso-type as a long-chain base and differ from each other in the length of the polymethylene chain of (2R)-2-hydroxy-fatty acids of the normal type: C23 in 8 and C24 in 9. All the new cerebrosides (4, 8, and 9) have β-D-glucopyranose as a monosaccharide residue. The composition of neutral sphingolipids from C. patagonicus was described for the first time. The investigated compounds 1–3, 5–7, and 9 exhibit slight to moderate cytotoxic activity against human cancer cells (HT-29, SK-MEL-28, and MDA-MB-231) and normal embryonic kidney cells HEK293. Compounds 2, 5, and 6 at a concentration of 20 µM inhibit colony formation of MDA-MB-231 cells by 68%, 54%, and 68%, respectively. The colony-inhibiting activity of compounds 2, 5, and 6 is comparable to the effect of doxorubicin, which reduces the number of colonies by 70% at the same concentration. [ABSTRACT FROM AUTHOR]

A coronene-like graphitic nanoribbon was recently synthesised as a potential candidate for applications in nanoelectornics due to its unique structural characteristics in contrast with other nanomaterials. It is a planar, thin, finite, and quasi-one-dimensional carbon-based material with novel characteristics. The coronene-like graphitic nanoribbon is constructed using multiple units of a finite dimensional coronene structure linked together in a chain of armchair and zigzag isomers. In this article, we compute the topological properties based on distance and degrees of armchair and zigzag nanoribbon isomers by adopting the orthogonal partition techniques. Our results on entropy measures demonstrate that armchair and zigzag nanoribbon isomers exhibit isentropic structures. We have computed the vertex partitions, 13 C NMR and ESR spectra using distance degree sequence vectors and spectra of armchair and zigzag isomers. Furthermore graph spectral properties of the two isomers are computed which reveal that the zigzag nanoribbons are kinetically more stable than the corresponding armchair isomers. [ABSTRACT FROM AUTHOR]

X-ray crystallography was used to characterise the title compound for the first time, and the 1H NMR, 13C NMR and IR spectroscopic data from earlier reports were also updated. [ABSTRACT FROM AUTHOR]

Reaction of ortho-carborane with anhydrous AlCl3 in chloroform results in a mixture of 9-chloro, 9,12-dichloro, and 8,9,12-trichloro derivatives with 9,12-dichloro-ortho-carborane being the main product. Molecular crystal structure of 9,12-dichloro-ortho-carborane was determined by the single crystal X-ray diffraction. The crystal structure of 9,12-Cl2-1,2-C2B10H10 appeared to be nearly isostructural to 9,12-dibromo-ortho-carborane: the crystal packing is built of layers in which molecules are connected via weak hydrogen and halogen bonds. A synthetic scheme for preparation of the hexachloro derivative of cobalt bis(dicarbollide) Cs[8,8′,9,9′,12,12′-Cl6-3,3′-Co(1,2-C2B9H8)2] from 9,12-dichloro-ortho-carborane has been proposed. [ABSTRACT FROM AUTHOR]

This study investigated the macro & micro properties of the composite gels formed by soy protein isolate (SPI) and peach pectin fractions: water-soluble pectin (WSP), chelator-soluble pectin (CSP), and sodium carbonate soluble pectin (NSP). Specially, the interaction between pectin fractions and SPI was studied to explain the formation mechanism of the composite gels. WSP, as a high methoxyl pectin, exhibited rich branching (sugar ratio B = 3.10). CSP, as a low methoxyl pectin, depicted a high linearity. NSP, with low linearity (sugar ratio A = 6.14), contained numerous side chains. Due to the strong interaction between pectin fractions and SPI, the new composites with excellent dense network microstructures were formed, accompanied by increased apparent viscosity, higher G' and G'', and reduced particle size. XRD and FT-IR analysis highlighted the modifications in gel structures. SEM-dispersive X-ray spectroscopy observed elemental distribution and framework composition in pectin-SPI gels. Hydrophobic interaction was the most important chemical force in pectin-SPI binding. Molecular docking results indicated that galacturonic acid in pectin bound more strongly to 7S than to 11S, with tighter hydrogen bonds. Notably, WSP-SPI showed the lowest turbidity, indicating enhanced solubility and particle dispersion, which helped prevent aggregation. CSP-SPI demonstrated the highest G' and G'', ascribing to the high linearity and abundant carboxyl groups in CSP. NSP-SPI showed the highest apparent viscosity and irregular structure. Overall, the texture properties of pectin-SPI gels were driven by pectin's structure properties, which would provide new and valuable information for texture control in gel formulation., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The emerging Schiff base‐derived metal complexes are the building blocks for biomedical applications. Herein, novel Schiff base N,N′‐[(1Z,2Z)‐1,2‐diphenylethane‐1,2‐diylidene]bis(6‐nitro‐1,3‐thiazol‐2‐amine) and corresponding Cu(II), Ni(II), Mn(II), and Co(II) metal complexes were successfully synthesized and characterized. The characterization of ligand and corresponding metal complexes was carried out by employing elemental analysis, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy, Fourier transform infrared spectroscopy (FTIR) analysis, molar conductance, magnetic susceptibility measurements, electronic spectra, electronic paramagnetic resonance (EPR) and density functional theory (DFT) studies. DFT calculations at B3LYP/6‐311+G** level of theory have been executed to examine the equilibrium geometry of the ligand and metal complexes. Furthermore, total energy, highest‐occupied molecular orbital (HOMO) and lowest‐unoccupied molecular orbital (LUMO), and Mulliken atomic charges were reckoned. Tetrahedral geometry was observed in the case of the Ni(II) complex, and octahedral geometries were discerned for Cu(II), Mn(II), and Co(II), complexes. Docking studies were performed against the newly synthesized analogs with the active site of Escherichia coli (PDB ID: 3t88), Staphylococcus aureus (PDB ID: 3q8u), Candida Albicans (PDB ID: 3qlw), and Aspergillus flavus (PDB ID: 4ynt) receptors to recognize the interactions between complexes and identify their probable binding sites. Synthesized analogs were examined for in vitro antimicrobial activity employing both minimum inhibitory concentration and disk diffusion method against the aforementioned pathogens. The result for these pathogens suggested metal compounds evince higher activity in comparison to the free ligand. [ABSTRACT FROM AUTHOR]

The results of studies of ion mobility and electrophysical properties of solid solutions containing bismuth trifluoride are analyzed and summarized. The influence of fluorides as constituents of solid solutions on the character of ion mobility and ionic conductivity is considered. Solid solutions with a conductivity of about 10−3−10−2 S cm−1 in the temperature range 400–550 K can be treated as promising basis for the synthesis of functional materials. [ABSTRACT FROM AUTHOR]

• Lithium niobate-borophosphate glasses were prepared and studied. • Crystallization studies showed the formation of NbOPO 4 compound within the whole compositional region. • Structural studies by 31P and 11B 1D/2D NMR spectroscopy resulted in the speciation of borate structural units. • Information from 2D maps made it possible to obtain an assignment of mixed borate-phosphate species formed in the glass network. Glasses in the series (100-x)[0.4Li 2 O-0.2Nb 2 O 5 -0.4P 2 O 5 ]-xB 2 O 3 were prepared with B 2 O 3 content ranging from 0 to 48 mol%. The glass transition temperature (T g) increases with up to 8 mol% B 2 O 3 , peaking at 512 °C, then decreases to 490 °C at 40 mol% B 2 O 3. Raman spectra at low B 2 O 3 content indicate the presence of NbO 6 octahedra. XRD patterns of crystallized samples reveal NbOPO 4 formation across the entire composition range. Confrontation of the Raman spectra of glasses and crystalized glasses resulted in the assignment of the broad Raman band at 777–804 cm−1 to Nb−O−Nb vibrations in the NbO 6 octahedra. 11B MAS NMR shows a transition from BO 4 to BO 3 units, while 31P MAS NMR suggests mixed borate-phosphate structures. Using 2D NMR techniques, mixed species were identified in the glass network. Ionic conductivity remained stable up to 16 mol% B 2 O 3 but decreased significantly at higher concentrations due to reduced Li+ ion mobility in the mixed phosphate-borate network. [ABSTRACT FROM AUTHOR]

• 3-, 4- and 6-methyl-5-nitropyridine thiols and disulfides were synthesized. • IR and Raman spectra were measured and analyzed using DFT approach. • 1H, 13C NMR and electron absorption and emission spectra were recorded. • FMO, NBO, Mulliken parameters and HOMO-LUMO values are related to experimental results. • Prospective applications of the studied derivatives is proposed. Three new methyl-nitropyridine-thiols were synthesized and their reaction to disulfide forms were studied. All synthesized compounds were characterised by means of structural and spectroscopic measurements. The structures were confirmed by XRD and NMR studies as well as IR, Raman, UV–VIS, and emission spectra. The analysis of the obtained results was carried out using quantum chemical DFT calculations. The vibrational characteristics were reported and a full set of the normal modes typical of the thiol and disulfide groups were identified and assigned to respective IR and Raman bands. The results of structural and spectroscopic studies were used to find the dependence between the optical properties and position of the methyl group in studied pyridine derivatives. The calculated singlet and triplet states of the electron spectra were analysed to identify the unique spectral pattern resulting from the electrons of the C-S-S-C bond in the heterocyclic derivatives. [Display omitted] [ABSTRACT FROM AUTHOR]

X-ray crystallography was used to characterise the title compound for the first time, and the 1H NMR, 13C NMR and IR spectroscopic data from earlier reports were also updated.

• Qn units' content shifts with F/O ratio, influencing structural properties. • Qualitative analysis reveals dominance patterns with varied F/O ratios. • Increasing F/O ratio yield a transition from Q2 to Q1, and subsequently to Q0 units. • Increasing F/O ratio leads to gradual decrease in the number of . • High F/O ratio reduces the available sites for F atoms substitution. Fluorophosphate glass has excellent characteristics such as low nonlinear refractive index, anomalous partial dispersion, low phonon energy, high UV transparency and high rare earth doping concentration, etc. The two anion ions of fluorine (F) and oxygen (O) and their F/O ratio in fluorophosphate glasses provide important structural characteristics of the specific glass. To explore this, a series of fluorophosphate glass samples with theoretical F/O ratios ranging from 1 to 7 were prepared, Raman spectroscopy and 31P nuclear magnetic resonance (NMR) spectroscopy were mainly employed to elucidate the structural polyhedrons made of the network chain. The underlying correlation between the Qn units and F/O ratio was explored, i.e., the Q2 unit dominate when the F/O ratio is less than 0.3, and predominantly Q2 or Q1 unit is predominant as F/O ratio ranges from 0.3 to 1, it comes to be Q1 or Q0 unit as F/O ratio further increase to 4, while it becomes Q0 when the F/O ratio is greater than 4. The applicability of this interval estimation was verified by comprehensive analyzing a variety of structural results of fluorophosphate glasses with various glass compositions. The explored interrelation between the F/O ratio and structural property is of great significance for developing low nonlinear and UV transparent fluorophosphate glasses. [ABSTRACT FROM AUTHOR]

Transformation of H2PtCl6 over time under the action of 2-octanol has been studied by NMR, IR spectroscopy, GLC, and GC/MS. It has been found for the first time that the alcohol in a H2PtCl6 ⋅ 6H2O–2-octanol solution is hydrochlorinated to give 2-chlorooctane. Dehydrated platinum chlorides catalyze the elimination of methyl groups in trimethylchlorosilane and hexamethyldisiloxane, which leads to the formation of polydimethylsiloxanes. It has been assumed that the resulting π-complex of H2PtCl4 with octene-1 is not stable in a hydrochloric medium and rapidly decomposes to release chloroalkyl. [ABSTRACT FROM AUTHOR]

The process of protonation of [2,6-B10H8O2CCH3]− was investigated both theoretically and experimentally. The most suitable conditions for protonation of the derivative [2,6-B10H8O2CCH3]− were found. The process of protonation was carried out in the presence of an excess of trifluoromethanesulfonic acid CF3SO3H at room temperature in dichloromethane solution. The structure of the resulting complex [2,6-B10H8O2CCH3*Hfac]0 was established using NMR data and the results of DFT calculations. An additional proton atom Hfac was found to be localized on one of the facets that was opposite the boron atom in a substituted position, and which bonded mainly with one apical boron atom. The main descriptors of the B-Hfac bond were established theoretically using QTAIM and NBO approaches. In addition, the mechanism of [2,6-B10H8O2CCH3]− protonation was investigated. [ABSTRACT FROM AUTHOR]

The synthesis and properties of titanium phosphonate cluster molecules have been investigated; however, nothing has been done to study not only the catalytic ability of a hydrolyzed cluster but also a behavior of hydrolysis–polycondensation by solvents. The sol–gel reaction of [Ti4(μ3‐O)(OiPr)5(μ‐OiPr)3(O3PPh)3]·thf (Ti4P3Ph) was performed in tetrahydrofuran (THF), toluene, and acetone. The hydrolysis–polycondensation of Ti4P3Ph proceeded in THF and toluene, while Ti4P3Ph in acetone proceeded in two paths (hydrolysis–polycondensation and nonhydrolysis–polycondensation). The hydrolyzed Ti4P3Ph retained its cluster structure, while the calcined Ti4P3Ph at 300°C contained a collapsed cluster structure. The specific surface areas of the hydrolyzed Ti4P3Ph in THF, toluene, and acetone were 154, 302, and 7 m2 g−1, respectively. The photodegradation ability of the hydrolyzed Ti4P3Ph for methylene blue was confirmed by ultraviolet irradiation at 365 nm; however, that of the calcined Ti4P3Ph was not. It was considered that the calcined Ti4P3Ph did not retain its cluster structure. The photocatalytic ability of the hydrolyzed Ti4P3Ph was high in the order of toluene > THF > pristine > acetone. The gels retained cluster structure have higher photocatalytic ability than pristine cluster; however, the gel contained a collapsed cluster structure was found no catalytic ability. [ABSTRACT FROM AUTHOR]

17O NMR spectra of pyridine N-oxide (PyO) complexes with the acids - acetic (AA), cyanoacetic (CyA), propiolic (PA), trichloroacetic (TCA), trifluoroacetic (TFA), hydrochloric (HCl) and methanesulfonic (MSA) - as well as some related molecules with intramolecular H-bonds (4-substituted picolinic acid N-oxides) were studied in an acetonitrile (ACN) solution. In order to evaluate the effect of proton positioning along the O-H...O bond on the measured chemical shifts the full geometry optimization was carried out, and 17O magnetic shielding tensors were calculated using density functional theory (DFT). The modified hybrid functional PBE1PBE with the 6-311++G** basis set and the gauge-including atomic orbital (GIAO) approach were applied. The solvent effect was taken into account by a polarized continuum model using the integral equation formalism (IEFPCM). Two stable structures were deduced for the PyO complexes with TCA and TFA that correspond to the H-bonds with and without proton transfer (PT). Two minima on the potential surface were separated by ca 0.2 Å. The experimental 17O NMR spectra have shown that the PyO-TCA complex in ACN can be considered as H-bonding with incipient PT, whereas it is known from neutron diffraction that in its crystalline state PT occurs. The proton location in PyO-TFA due to the thermally induced proton sharing was found at the middle point. The 17O NMR data for the acids with an intramolecular H-bond (nitroPANO, PANO and methoxyPANO) deviate from the general trend. The factors that can cause it, such as the substitution effect, persistence of nano-crystallites in a solution due to a low solubility, etc., have been discussed. [ABSTRACT FROM AUTHOR]

Synthesis, NMR spectral data and crystal structure of 9,12-dibromo derivative of ortho-carborane are reported. [ABSTRACT FROM AUTHOR]