Sonochemical synthesis of a two‐dimensional supramolecular polymer with nanoporous morphology,linear thallophilic and covalent hydrogen‐bonding interactions

A new thallium‐based supramolecular polymer [Tl(μ₃–3‐HClb)(μ₃–3‐Clb)]_n ( 1 ), (3‐HClb = 3‐chloroperbenzoic acid), has been synthesized and structurally characterized by single crystal X‐ray crystallography. It has a two‐dimensional structure with linear thallophilic and covalent hydrogen‐bonding interactions. In order to evaluate the effects of concentration, ultrasonic irradiation and type of solvents on structure, morphology and thermal behavior of 1 , some experiments were designed, and eight samples of 1 were synthesized under different conditions. These samples were characterized by IR spectroscopy, thermogravimetric and differential thermal analyses, X‐ray powder diffraction and scanning electron microscopy.     

Glassy carbon electrode modified by new Copper(I) oxide nanocomposite for glucose detection: An electroanalysis study

The Glucose amount of human blood is very vital because in higher levels than allowed value the corporal biological system was hampered. Therefore, in this study, the Cu₂O was deposited on the reduced Graphene oxide (RGO) by polydopamin (PDA) as linker. The new RGO‐PDA‐Cu₂O nanocomposite was deposited on the glassy carbon electrode (GCE) surface after its characterization by UV–Visible, fourier transform infrared (FT‐IR), X‐ray diffraction (XRD), Energy‐dispersive X‐ray (EDX), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) techniques. The electroanalysis of the new electrode was investigated by the cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) methods. The obtained detection limit of glucose (Glu) showed that the deposited GCE by RGO‐PDA‐Cu₂O nanocomposite has a high potential for its diagnosis. In addition, this electrode was applied to the Glu detection as biosensor in real samples in order to utilize in commercial applications.     

An Experimental and Theoretical Study on Influence of H‐bonding on the Synthesized Azo Derivatives Structures

We have reported a simple and efficient reaction for the synthesis of some new functionalized azo structures which were prepared by electron deficient acetylenic compounds in the presence of triphenylphosphine. The characterization of the synthesized azo compounds has been determined by FTIR, UV‐Vis, ¹H NMR, ¹³C NMR and Mass spectroscopic techniques. The influence of H‐bonding on the products has been shown by different experimental analysis. Also, the regioselectivity of the reaction, tautomerization equilibrium and the stability of products was investigated using DFT calculations at the B3LYP/6‐31G level of theory.     

Human serum albumin binding studies of a new platinum(IV) complex containing the drug pregabalin: experimental and computational methods

A new platinum(IV) complex, [Pt(en)(Cl)₂(Pregabalin)₂], containing the drug pregabalin was synthesized and characterized by elemental analysis, FT-IR, ¹H NMR, mass spectrum, thermogravimetric analysis (TGA), molecular docking and RHF/PM6 method. Also, the interaction of Pt(IV) complex with human serum albumin (HSA) was studied by using UV–vis, fluorometric, circular dichroism (CD) spectroscopies and molecular docking techniques. The results demonstrated that the binding of the complex to HSA caused strong fluorescence quenching of HSA through static quenching mechanism. Hydrogen bonds and van der Waals contacts are the major forces in the stability of protein-Pt(IV) complex and the process of the binding of complex with HSA was enthalpy driven (ΔH = –105.8?kJ·mol^?1). The results of CD and UV–vis spectroscopy indicated that the binding of the complex to HSA caused conformational changes in HSA. In addition, the study of molecular docking and RHF/PM6 method confirm the experimental results with respect to the mechanism of binding.     

Green conversion of a three‐dimensional organometallic coordination polymer to a three‐dimensional organometallic supramolecular polymer upon mechanochemical 2‐aminopyridine addition

Green conversion of three‐dimensional organometallic [Ag₂(μ₆‐tp)]_n ( 1 ) coordination polymer (CP) nanosheets, prepared by sonochemical procedure, to three‐dimensional organometallic [Ag₂(μ₄‐tp)(apy)₂]_n ( 2 ) (where H₂tp = terephthalic acid and apy = 2‐aminopyridine) CP nanoparticles has been observed upon solid‐state mechanochemical reaction of compound 1 with 2‐aminopyridine. The AgO₃ Ag ···C₆ coordination sphere of silver ion in 1 changed to NO₂ Ag ···C coordination sphere in 2 during this mechanochemical addition. These samples were characterized by infrared spectroscopy, thermogravimetric and differential thermal analyses, X‐ray powder diffraction and scanning electron microscopy.     

ZnO nanoparticles as chain elasticity reducer and structural elasticity enhancer: Correlating the degradating role and localization of ZnO with the morphological and mechanical properties of PLA/PP/ZnO nanocomposite

The main purpose of this study was to investigate the effect of zinc oxide (ZnO) nanoparticles on the morphological, mechanical, thermal, and rheological properties of PLA/PP blend. In this regard, nanocomposites containing 1, 3, and 5 wt% of ZnO nanoparticles were prepared by melt mixing. In addition, three different mixing procedures were adopted to study their effects on the microstructure of nanocomposites. The rheological behaviors demonstrated a higher elasticity and less compatibility for two phases in the case of nanocomposites containing nanoparticles in harmony with the morphological observations. Accordingly, it was correlated to the elasticity originating from the interphase, anticipated coalescence of dispersed particles as a result of degradation of PLA chains triggered by ZnO nanoparticles (ZnO‐NPs) and also agglomeration of ZnO‐NPs depending on the content of nanoparticles and chosen mixing procedure. It was also found that mixing method puts a remarkable influence on the microstructure and rheological behavior of nanocomposites. Results of mechanical characterizations and thermogravimetric analysis (TGA) also confirmed the degradation induced by ZnO nanoparticles.     

Chemoselective synthesis of xanthenes and tetraketones in a choline chloride-based deep eutectic solvent

A chemoselective synthesis of tetraketone and xanthene derivatives, by means of tandem Knoevenagel condensation and Michael addition in choline chloride-based deep eutectic solvents (DESs), is presented. The reaction of readily available aldehydes and active methylene compounds in malonic acid- and ZnCl₂-based DES gives various xanthenes derivatives with good to excellent yields under mild reaction conditions. On the other hand, tetraketones were synthesized in almost quantitative yields by simple condensation of an aldehyde and active methylene compounds in milder deep eutectic solvents of urea and SnCl₂. In addition, the reaction of other types of choline chloride-based DES leads to a mixture of tetraketone and xanthene.     

Efficient purification and complete NMR characterization of galactinol,sucrose, raffinose,and stachyose isolated from Pinus halepensis (Aleppo pine) seeds using acetylation procedure

The use of precipitation followed by acetylation procedures and preparative TLC purification allowed a facile isolation of four carbohydrates from the methanol extract of Pinus halepensis seeds. The isolated oligosaccharides exhibited high degree of purity. They were identified as α-D-galactosyl-(1→1)-myo-inositol nonaacetate (1), α-D-glucosyl-(1→2)-β-D-fructosyl octaacetate (2), α-D-galactosyl-(1→6)-α-D-glucosyl-(1→2)-β-D-frutosyl undecaacetate (3), and α-D-galactosyl-(1→6)-α-D-galactosyl-(1→6)-α-D-glucosyl-(1→2)-β-D-frutosyl tetradecaacetate (4) and were isolated for the first time from this plant. The ¹H and ¹³C NMR assignments for compounds 2, 3, and 4 were detailed herein for the first time.     

Complexes of 2,5-dihydroxy-1,4-benzoquinone and chloranilic acid with second and third row transition elements

The synthesis of new 2,5-dihydroxy-1,4-benzoquinone (H2DHBQ) and chloranilic acid (H2CA) complexes cis-[Mo2O5L2]2– (L = DHBQ, CA), [W2O5(DHBQ)2]2–, [WO2(CA)2]2–, trans-[UO2(DHBQ)]·H2O, and trans-[UO2(CA)2]2– is described. Raman, i.r., 1H and 13C n.m.r spectra of the ligands and their complexes are reported and their structures discussed.     

Magnetic solid-phase extraction of organophosphorus pesticides from apple juice and environmental water samples using magnetic graphene oxide coated with poly(2-aminoterephthalic acid-co-aniline) nanocomposite as a sorbent

An effective magnetic solid-phase extraction method was proposed using magnetic graphene oxide coated with poly(2-aminoterephthalic acid-co-aniline) as a sorbent for preconcentration and extraction of organophosphorus pesticides from environmental water and apple juice samples, and determined using the gas chromatography-mass spectrometry analysis. To approve the successful synthesis of the magnetic nanocomposite, the prepared sorbent was characterized by field emission scanning electron microscopy, X-ray diffraction, vibrating sample magnetometer, and Fourier transforms infrared techniques. The main parameters affecting the extraction efficiency were considered and studied to afford an optimized procedure. Systematic method validation verified its suitable recoveries (89.4–107.3%), and precision (relative standard deviations < 6.8%). The method showed a wide linear dynamic range (0.04–700 ng/mL) with low limits of detection (0.01–0.06 ng/mL) and quantification (0.04–0.21 ng/mL). This method presented good potential and great sensitivity for the pesticides determination.