Search

In this study, new 2-Hydroxy-1-naphthaldehyde linked magnetic Fe3O4/chitosan-polyacrylamide nanoparticles were prepared. The synthesized nanoparticles were characterized by (FT- IR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), vibrating Sample Magnetometry (VSM) and Termogravimetric Analysis (TGA). The 2-Hydroxy-1-naphthaldehyde modified magnetic Fe3O4/chitosan-polyacrylamide nanoparticles were used as an effective adsorbent for removal of Everzol black from aqueous solutions by batch adsorption procedure. The effects of important parameters on the surface absorption process of Everzol black dye, including pH, contact time, adsorbent dosage and initial dye concentration were studied. The Langmuir and Freundlich adsorption models were used to describe adsorption isotherms and constants.

Co(II) macrocyclic Schiff base complex nanoparticles have been encapsulated in the nanopores of zeolite Y. The new Schiff base complexes entrapped in the nanoreactor of zeolite Y were characterized by several techniques: chemical analysis and spectroscopic methods (FT-IR, XRD, and DRS). These complexes (neat and encapsulated) were used for epoxidation of alkenes with O2 as oxidant in different solvents. The catalyst demonstrated excellent activity for a variety of alkenes in a mild, inexpensive and efficient protocol. Reaction parameters including temperature, catalyst amount and solvent were screened by reaction time. The recycling experiment results indicated that the catalysts were highly stable and maintained activity and selectivity even after being used for five cycles.

A thermal-responsive Y-shaped amphiphilic block copolymer, namely poly(N-isopropylacrylamide-block-[poly(e-caprolactone)]2 (PNIPAAm-b-PCL2), was synthesized through the combination of atom transfer radical polymerization (ATRP) and ring-opening polymerization (ROP) techniques, and its potential as smart anti-cancer drug delivery system was investigated preliminary. The fabricated polymers were characterized using FTIR and 1H NMR spectroscopy, and GPC analysis. The self-assembly behavior of the fabricated PNIPAAm-b-PCL2 copolymer under thermal stimuli was investigated using dynamic light scattering and UV–Vis spectroscopy. The lower critical solution temperature of the synthesized PNIPAAm-b-PCL2 was found to be 39–41°C. The doxorubicin hydrochloride loading and encapsulation capacities of the fabricated PNIPAAm-b-PCL2 were calculated to be 62 ± 3%, and 75 ± 4%, respectively; the drug release value was up to 46.5% during 40 h at 37°C and up to 88% at 40°C.

N,N,N',N'-tetramethyl-N,N'-bis(sulfo)ethane-1,2-diaminium mesylate ‎‎([TMBSED][Oms]2) is ‎used as a highly efficient and dual-functional catalyst for the one-pot multi-component ‎condensation of 2-naphthol with arylaldehydes and thioacetamide under green, mild (70 °C), ‎and solvent-free conditions. In this reaction, 1-thioamidoalkyl-2-naphthols are produced in ‎high to excellent yields and in relatively short reaction times. In this reaction, products ‎are identified by analysis of its 1H NMR, 13C NMR, and FT-IR data.‎ Moreover, a plausible mechanism based on dual-functionality of the catalyst was proposed.

Mo(VI) tetradentate Schiff base complexes were covalently immobilized onto chemically functionalized graphene oxide (GO) using 3-(tri-methoxysilyl) propylamine as a coupler. The resulting heterogen...

Transition-metal catalyzed cross-dehydrogenative-coupling reactions encompass highly versatile and atom economical methods for the construction of various carbon–carbon and carbon–heteroatom bonds by combining two C(X)–H (X = heteroatom) bonds. Along this line, direct acyloxylation of C–H bonds with carboxylic acids has emerged as a powerful and green approach for the synthesis of structurally diverse esters. In this focus-review we will describe recent progress in direct esterification of aromatic C–H bonds with special emphasis on the mechanistic features of the reactions. Literature has been surveyed until the end of February 2019.

This review is an attempt to give an overview on the recent advances and developments in the synthesis of 2-oxazolidinone frameworks through carbon dioxide (CO2) fixation reactions under solvent-free conditions. The cycloaddition of CO2 to aziridine derivatives is discussed first. This is followed by carboxylative cyclization of N-propargylamines with CO2 and three-component coupling of epoxides, amines, and CO2. Finally, cycloaddition of CO2 to propargylic alcohols and amines will be covered at the end of the review. The literature has been surveyed up until the end of 2018.

A simple, cheap and efficient method for pre-concentrating and separating Zn(II) ions from aqueous solutions and real samples has been designed. The method was implemented in a prototype featuring interchangeable chromatography-column-like cartridges, filled with meso-porous silica nanostructures, allowing easy exchange of the type and quantity of the sorbent. The adsorbents inside the column are held in place by means of porous polymer nano-fibre membranes. The effects of various parameters on the adsorption of Zn(II) ions from aqueous solutions were investigated. Maximal adsorption (∼99%) was found for Zn(II) ions amongst a mixture of Cu(II), Co(II), Ni(II), Ag(I), Au(III), Pd(II) and Pb(II) in aqueous solution. The procedure was tested for pre-concentrating and determining traces of zinc in real samples of meat, fish and hen marketed in Tehran. A desorption process using 0.5 mol L−1 HCl as eluent, showed ∼97% recovery of the Zn(II) ions adsorbed on the MSMPP sorbent.

In the current work, 2,2’-(butane-1,4-diylbis(oxy))dibenzaldehyde cross-linked magnetic chitosan nanoparticles (Fe3O4@CS-BAL) were successfully synthesized as the new magnetic adsorbent through crosslinking modification of magnetic chitosan nanoparticles (Fe3O4@CS) using 2,2’-(butane-1,4-diylbis (oxy))dibenzaldehyde (BAL) as a crosslinker at room temperature. The chemical structure, surface properties and morphology of the synthesized nanoparticles were characterized by Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD) and Scanning electronic microscope (SEM), Thermogravimetric analysis (TGA) and N2 adsorption-desorption isotherms. The 2,2’-(butane-1,4-diylbis(oxy))dibenzaldehyde-modified magnetic chitosan nanoparticles (Fe3O4@CS-BAL) were used as an effective adsorbent for removal of an anionic reactive dye, Reactive red 239 (RR239) from aqueous solutions by batch adsorption procedure. The effects of various experimental parameters such as adsorbent dosage, pH, contact time and initial dye concentration on the RR239 adsorption onto the Fe3O4@CS-BAL were investigated and optimized. The Langmuir and Freundlich adsorption models were used to describe adsorption isotherms and constants. The equilibrium results revealed that the adsorption behavior of the RR239 dye on the Fe3O4@CS-BAL nanoparticles fitted well with the Langmuir model. On the basis of the Langmuir analysis, the maximum adsorption capacity (qm) of the Fe3O4@CS-BAL for RR239 was found to be 200 mg/g. The experimental results showed that the Fe3O4@CS-BAL could be remove more than 99% of investigated dye within the first 2 min of contact time. Therefore, the Fe3O4@CS-BAL adsorbent can be successfully applied as an efficient and low-cost adsorbent for removal of anionic reactive dyes from aqueous solutions.

A novel dicationic ionic liquid, N,N,N′,N′-tetramethyl-N,N′-bis(sulfo)ethane-1,2-diaminium mesylate [TMBSED][OMs]2), has been produced, and identified by analysis of its 1H NMR, 13C NMR, FT-IR, mass and thermal gravimetric data. Thereafter, it has been utilized as a highly effectual, homogeneous and dual-functional catalyst to promote the multi-component reaction of ethyl acetoacetate, hydroxylamine hydrochloride and arylaldehydes under solvent-free conditions for the synthesis of 3-methyl-4-arylmethylene-isoxazole-5(4H)-ones. Due to the dual-functionality of [TMBSED][OMs]2 (possessing acidic and basic sites), and also having two sites of each, it was a highly effective and general catalyst for the synthesis. Moreover, a plausible and attractive mechanism based on the dual-functionality of the catalyst has been proposed.

In this study, a home-made device comprising a column filled with magnetic mesoporous silica-coated nanostructures (MSCM-PA) as an adsorbent was constructed and used to remove organic pollutants from aqueous solutions. The MSCM-PA adsorbent was prepared and characterized using Fourier transform-infrared spectroscopy, ultraviolet–visible spectroscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, vibrating sample magnetometry, Brunauer–Emmett–Teller, thermogravimetric analysis/differential thermal analysis, and powder X-ray diffraction techniques. The adsorption behavior of the MSCM-PA sorbent was studied based on the removal of Everzol blue dye from aqueous solutions. We investigated the effects of various parameters such as the solution pH, initial dye concentration, adsorbent dose, flow rate, and contact time on the adsorption of Everzol blue from aqueous solutions. The adsorption data were modeled using Langmuir and Freundlich isotherms, and a good fit was obtained with the Langmuir isotherm. The maximum Everzol blue adsorption capacity by MSCM-PA was 162 mg g−1. The results indicate that our device is capable of adsorbing anionic dyes from aqueous solutions.

In this study, a new sorbent was prepared by the chemical modification of silica gel with 2,2′-(hexane-1,6-diylbis(oxy))dibenzaldehyde (SiO2-NH2-BH) through a Schiff base bond formation by a normal method and a vice versa method. The structure and morphology of the synthesized materials were characterized by Fourier Transform Infrared (FT-IR), Scanning Electron Microscopy (SEM), Thermogravimetric Analyzes (TGA) and Ultraviolet Visible (UV–vis). The produced modified silica gel with normal method was used as an efficient adsorbent for the removal of two anionic reactive dyes, namely Reactive Yellow 84 (RY84) and Reactive Blue 19 (RB19) from their aqueous solutions by batch adsorption procedure. The effect of various operation parameters such as adsorbent dose, solution pH, solution temperature, initial dye concentration and contact time on the adsorption behavior of both the anionic dyes was investigated. The experimental data were analyzed by the Langmuir and Freundlich adsorption models. Based on the correlation coefficient values, it is observed that Langmuir isotherm is appropriate model to explain the adsorption isotherm of both the anionic dyes on SiO2-NH2-BH. The maximum adsorption capacities for Reactive Yellow 84 (RY84) and Reactive Blue 19 (RB19) dyes under room temperature were found to be 68.02 and 72.99 mg/g, respectively. The optimized pH for the effective removal of Reactive Yellow 84 (RY84) and Reactive Blue 19 (RB19) dyes were obtained at 6 and 4, respectively. Meanwhile, different thermodynamic parameters such as the Gibbs free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) were evaluated and the results indicated that the adsorption of both investigated dyes was a spontaneous and endothermic process in nature. Therefore, the silica modified with 2,2′-(hexane-1,6-diylbis(oxy))dibenzaldehyde can be employed as an effective and inexpensive adsorbent for the removal of anionic reactive dyes from aqueous solutions.

Two new adsorbents were synthesized by covalently grafting 2,3-Bis(2-formylphenoxy)-propan-1-ol (BH) onto the surface of silica-coated magnetic nanoparticles and silica gel by a conventional method and a vice-versa method. The morphology and properties of the adsorbents were characterized by FT-IR, XRD, SEM, TEM, VSM, TGA, UV-Vis, Optical microscope and DLS. The materials are shown to be effective adsorbents for the selective extraction of the ions of Au(III), Pd(II) and Ag(I) from aqueous mixed metal ions solution also containing Cu(II), Co(II), Ni(II), Zn(II) and Pb(II). Syringe and batch techniques are compared. The ions can be desorbed with 0.5 M HCl and quantified by FAAS. The maximum adsorption capacity of the MN-Si-NH2-BH and Si-NH2-BH were determined to be 257, 197 mg·g−1 for Au(III), 311, 191 mg·g−1 for Ag(I) and 301, 222 mg·g−1 for Pd(II), respectively. The detection limits (for n = 15 and at an S/N ratio of 2 blank standard deviations) are 0.12, 0.28, and 0.17 μg·L−1 for Au(III), Pd(II) and Ag(I), respectively.

The 2,2′-(pentane-1,5-diylbis(oxy))dibenzaldehyde (BP) functionalized silica gel (Si-APTES-BP) was synthesized successfully by a normal method and a inverse method. These new materials were characterized by Fourier Transform Infrared (FT-IR), Scanning Electron Microscopy (SEM), Thermogravimetric Analyzes (TGA) and Ultraviolet Visible (UV–vis). The modified silica gel with normal method was used as a sorbent for removal of anionic reactive dyes Reactive Blue 19 (RB19) and Reactive Yellow 84 (RY84) from their aqueous solutions by batch adsorption procedure. The batch adsorption experiments were performed to study the effect of various experimental parameters such as the solution pH, contact time, initial dye concentration, adsorbent dose and temperature. The results showed that the adsorption capacity of RB19 and RY84 dyes were enhanced with increase temperature of solution. The maximum uptake value for RB19 and RY84 dyes were obtained at pH 5 and pH 8, respectively. The isotherm data of both investigated dyes were analyzed by the Langmuir and Freundlich adsorption models. Based on the correlation coefficient values, it has been deduced that the Langmuir model is better fitted to the experimental data. The Langmuir maximum adsorption capacity of the Si-APTES-BP at 298 K was found to be 37.45 for RB19 and 32.36 mg/g for RY84, respectively. In addition, thermodynamic studies were conducted to calculate the changes in Gibbs free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°). The negative values of ΔG° and the positive value of ΔH° indicated that the adsorption process of both investigated dyes was a spontaneous and endothermic process in nature. The reusability of Si-APTES-BP has proven that the adsorbent is durable and cost-effective. Therefore, the silica gel modified with 2,2′-(pentane-1,5-diylbis(oxy))dibenzaldehyde can be used as an effective adsorbent for the removal of anionic reactive dyes from aqueous solutions.

In the present study, nano-sized titanium oxides were applied for preconcentration and determination of Pb(II) in aqueous samples using hollow fiber based solid-liquid phase microextraction (HF-SLPME) combined with flame atomic absorption spectrometry (FAAS). In this work, the nanoparticles dispersed in caprylic acid as an extraction solvent was placed into a polypropylene porous hollow fiber segment supported by capillary forces and sonification. This membrane was in direct contact with solutions containing Pb (II). The effect of experimental conditions on the extraction, such as pH, stirring rate, sample volume, and extraction time were optimized. Under the optimal conditions, the performance of the proposed method was investigated for the determination of Pb (II) in food and water samples. The method was linear in the range of 0.6–3000 μg mL−1. The relative standard deviations and relative recovery of Pb (II) was 4.9% and 99.3%, respectively (n = 5).

In this paper, new (2E, 2'E)-3, 3'-(((3- hydroxypropane-1, 2-diyl) bis (oxy)) bis (2, 1-phenylene)) bis (1-phenylprop-2-en-1-one) (2a) was prepared in good yield by condensation reaction of acetophenone with bisaldehyde (1a) in ethanolic NaOH solutions at room temperature. The (2E, 2'E)-3, 3'-(((3- hydroxypropane-1, 2-diyl) bis (oxy)) bis (2, 1-phenylene)) bis (1-phenylprop-2-en-1-one) (2a) was immediately reacted with phenyl hydrazine under refluxing conditions in the presence of potassium hydroxide to obtain the corresponding 2, 3-bis (2-(1, 3-diphenyl-4, 5-dihydro-1H-pyrazol-5-yl) phenoxy) propan-1-ol (3a). The newly synthesized compounds confirmed by melting point and TLC and their structure were established by various analytical techniques such as IR, 1H-NMR, 13C-NMR and elemental analysis.

A new series of spiro[[1,3]dithiolane-2,3′-indolines]-2′-one derivatives was synthesized using Michael addition reaction of spiro[[1,3]dithiolane-2,3′-indolin]-2′-one to various α,β-unsaturated esters as well as direct alkylation of this compound with alkyl dihalides. Michael reaction of spiro[[1,3]dithiolane-2,3′-indolin]-2′-one and α,β-unsaturated esters produced related Michael adduct in the presence of tetrabutylammonium bromide and base 1,4-diazabicyclo[2.2.2]octane in good to excellent yields at 80°C under solvent-free conditions. Also, direct alkylation of spiro[[1,3]dithiolane-2,3′-indolin]-2′-one by dihaloalkanes in the presence of base K2CO3 afforded the corresponding products in good yields under the same conditions.

Transition-metal catalyzed cross-dehydrogenative-coupling reactions encompass highly versatile and atom economical methods for the construction of various carbon-carbon and carbon-heteroatom bonds by combining two C(X)-H (X = heteroatom) bonds. Along this line, direct acyloxylation of C-H bonds with carboxylic acids has emerged as a powerful and green approach for the synthesis of structurally diverse esters. In this focus-review we will describe recent progress in direct esterification of aromatic C-H bonds with special emphasis on the mechanistic features of the reactions. Literature has been surveyed until the end of February 2019.

This review is an attempt to give an overview on the recent advances and developments in the synthesis of 2-oxazolidinone frameworks through carbon dioxide (CO

Two novel dithiophosphonate ligands, HS2P(p-C6H4OMe)(OCH2CH2CH(CH3)2) (1) and HS2P(p-C6H4OMe)(OCH(CH3)2) (2), were synthesized and characterized by multinuclear (1H, 31P, and 13C) NMR, infrared spectroscopy as well as elemental analysis. The reactions of 1 and 2 with NiCl2·6H2O and Cd(NO3)2·4H2O in methanol led to novel complexes 3 and 4. The single crystal X-ray structures of 3 and 4 showed tetracoordinated structure with square planar geometry for the nickel complex, while it showed pentacoordinated structure with distorted square-pyramid environment for the cadmium complex.

New 6-(hydroxymethyl)-14, 16-dimethyl-13, 14, 16, 17-tetrahydro-6H-13, 17-epiminodibenzo [e, l] [1, 4] dioxacyclotridecin-15 (7H)-one (2a) was synthesized in good yield by the Petrenko–Kritchenko reaction of 2, 2'-((3-hydroxypropane-1, 2-diyl) bis (oxy)) bisbenzaldehyde (1a) with diethyl ketone in the mixture of ethanol and acetic acid as solvent in the presence of ammonium acetate. The compounds were characterized by elemental analyses, IR, 1H-NMR, 13C-NMR and mass spectrometry.Keywords: Petrenko–Kritchenko condensation, Macrocyclic compound, Bisaldehyde, 6-(hydroxymethyl)-14, 16-dimethyl-13, 14, 16, 17-tetrahydro-6H-13, 17-epiminodibenzo [e, l] [1, 4] dioxacyclotridecin-15 (7H)-one, 2, 2'-((3 hydroxypropane-1, 2-diyl) bis (oxy)) bisbenzaldehyde

In this paper, a new series of five-membered heterocyclic compounds containing pyrazoline and pyrimidine nucleus were synthesized under both conventional and ultrasonic irradiation conditions. In the first step, bischalcone derivatives were prepared by Claisen-Schmidt condensation of bisaldehydes and acetophenone in alkaline ethanol under conventional and ultrasonic conditions. In the second step, bispyrimidine and bispyrazolines were synthesized by the condensation reaction of bischalcones with thiourea/phenyl hydrazine in an alkaline medium. The ultrasound-assisted synthesis provides excellent yields in short reaction times at room temperature. The structures of the newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR, mass and elemental analysis. The new synthesized bispyrimidine and bispyrazoline were used as new adsorbents for the excellent selective removal of silver and lead ions from aqueous mixed metal ion solution containing Cu(II), Co(II), Ni(II), and Zn(II) by batch technique. Also, the quantitative desorption was achieved for lead and silver ions with 0.5 M of HNO3 and HCl solutions, respectively.

Quantitative structure-activity relationship (QSAR) models were employed for prediction the activity of P2X7 receptor antagonists. A data set consisted of 50 purine derivatives was utilized in the model construction where 40 and 10 of these compounds were in the training and test sets respectively. A suitable group of calculated molecular descriptors was selected by employing stepwise multiple linear regressions (SW-MLR) and genetic algorithm-multiple linear regressions (GA-MLR) as variable selection tools. The proposed MLR models were fully confirmed applying internal and external validation techniques. The obtained results of this QSAR study showed the superiority of the GA-MLR model over the SW-MLR model. As a result, the obtained GA–MLR model could be applied as a valuable model for designing similar groups of P2X7 receptor antagonists.

In the present study, magnetite nanoparticles (MNPs) were synthesized at room temperature under ultrasonic irradiation. The synthesized MNPs were then silylated with triethoxyvinylsilane to give a core-shell structure containing vinyl moieties on the surface. Encapsulation of the MNPs in a polysiloxane shell was clearly shown by transmission electron microscopy (TEM). The radical polymerization of the silylated product with vinyl acetate (VAc) leads to the formation of polymer nanocomposites (PN) in which some of the polymer chains are chemically grafted onto the MNPs. The homopolymer (PVAc) formed during polymerization was separated from the grafted MNPs using Soxhlet extraction. Chemical grafting of the polymer onto the MNPs was confirmed by Fourier transform infrared spectroscopy (FTIR). The amount of grafted polymer was calculated using thermogravimetric analysis (TGA). The thermal properties of the prepared MNPs, silylated MNPs, PVAc-grafted MNPs and PNs were studied using TGA. The MNPs and the nanocomposite containing 15 wt% of the PVAc-grafted MNPS (PN 15 wt%) were further investigated by scanning electron microscopy (SEM), TEM, XRD and energy dispersive X-ray analysis (EDAX). Vibrating sample magnetometry (VSM) showed the unique phenomenon of superparamagnetism for the prepared MNPs, silylated MNPs and PVAc-grafted MNPs.

One-pot, two-step synthesis of several 1-cyclopropanecarbonyl-3-(substituted phenyl)-thioureas and 1-(phenylene-1,4-dione)-3,3′-(substituted phenyl)-dithioureas have been successfully prepared. The structures of the synthesized compounds were confirmed by elemental analysis, FT-IR spectroscopy and NMR. Also the crystal structure one of these compounds was determined by X-ray crystallography. All synthesized compounds were evaluated for antibacterial activity using Salmonella enterica (SE), Micrococcus luteus (ML), Bacillus subtilis (BS) and Pseudomonas aeruginosa (PS).

The binuclear complex of the type Cd2(HL)4 was isolated from the reaction of cadmium(II) nitrate and dithiophosphonate ligands of the type R1R2PSSH ( R1 = CH3OC6H4 and R2 = (CH3)2CHCH2CH2O). The crystal structure of bis-{bis-[O-3-methylbutyl (4-methoxyphenyl) dithiophosphonato] cadmium(II)}, Cd2(HL)4, has been determined by means of single-crystal X-ray diffraction methods. The cadmium is tetra-coordinated structure and constitutes a nearly planar geometry with the atoms on the PS2 group of the ligand. The nanoparticles of the complex were also prepared by ultrasonication, and their SEM micrographs indicated identical spherical morphologies with particles sizes about 32–39 nm. The complex and ligand were additionally tested in view of their antibacterial properties. The cadmium(II) dithiophosphonato complex was found to be more active against E. coli and S. aureus than free ligand.

The predictive analysis based on quantitative structure activity relationships (QSAR) on benzimidazolepyrrolidinyl amides as prolylcarboxypeptidase (PrCP) inhibitors was performed. Molecules were represented by chemical descriptors that encode constitutional, topological, geometrical, and electronic structure features. The hierarchical clustering method was used to classify the dataset into training and test subsets. The important descriptors were selected with the aid of the genetic algorithm method. The QSAR model was constructed, using the multiple linear regressions (MLR), and its robustness and predictability were verified by internal and external cross-validation methods. Furthermore, the calculation of the domain of applicability defines the area of reliable predictions. The root mean square errors (RMSE) of the training set and the test set for GA-MLR model were calculated to be 0.176, 0.279 and the correlation coefficients (R 2) were obtained to be 0.839, 0.923, respectively. The proposed model has good stability, robustness and predictability when verified by internal and external validation.

The characterization of an optode is described for detection of copper(II) based on the immobilization of 6-bromo-3-(2-methyl-2,3-dihydrobenzo[d]thiazol-2-yl)-2H-chromen-2 one on a triacetylcellulose membrane. The effects of pH, indicator concentration and reaction time on the immobilization of ligand were studied. This optode can readily be regenerated using thiourea solutions and its response was reproducible and reversible (R.S.D. less than 2.7%). The Cu(II) could be determined in the range between 7.0 × 10−7 and 1.0 × 10−4 M with a detection limit of 2.5 × 10−7 M. The optical sensor was successfully applied for the determination of copper(II) in various real samples.

Quantitative structure property relationship study of Fullerene derivatives was studied to predict the power conversion efficiency of compounds as polymer solar cell acceptors. The data set was split into the training and test set by employing hierarchal cluster technique. The most relevant descriptors were selected using the genetic algorithm (GA) method. The predictive ability of the constructed model was evaluated using Y -randomization test, cross-validation and test set compounds. The GA–MLR model was built based on six molecular descriptors, and it revealed appropriate statistical results. The results suggested that some quantum-chemical descriptors play significant effects on increasing the PCE values.

This work reports the synthesis and application of Au/Pd nanoparticles as separable catalysts for Heck coupling reactions in water under aerobic conditions. This method provides high yields, mild reaction conditions, and an easy work-up. Catalytic efficiency remains unaltered even after several repeated cycles.

In this study, new silica-coated magnetic nanoparticles modified with bisaldehyde (BISA–APTSCMNPs) were synthesized using a normal method and a vice versa method. The crystal structure of the newly obtained nanoparticles was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Vibrating Sample Magnetometry (VSM), thermogravimetric analysis (TGA) and ultra-violet visible spectroscopy (UV-vis). The surface of the nanoparticles was modified with bisaldehyde (BISA–APTSCMNPs), and these were used for the highly selective removal of Ag(I) ion from an aqueous mixed metal ion solution containing Cu(II), Co(II), Ni(II), Zn(II) and Pb(II) using the syringe and batch techniques. Moreover, the silver ion desorption was most efficient in HCl.

The simultaneous spectrophotometric determination of ceftazidime (CTZ) and sulbactam (SBT) in the presence of the overlapping spectra were accomplished with the partial least squares (PLS) and genetic algorithm-partial least squares (GA-PLS) approaches. In this study, the calibration set was based on the absorption spectra in the range of 230–350 nm for 25 different mixtures of CTZ and SBT. The calibration curve was linear over the concentration range of 2–30 and 4–46 μg mL−1 for CTZ and SBT, respectively. These two methods were tested by analyzing the synthetic mixtures of the CTZ and SBT and they were applied to real samples containing a commercial pharmaceutical preparation of the subject drugs. Good results were obtained by the two methods. However, the accuracy of the GA-PLS method was better than that of the PLS method.

In this study, the quantitative structure–activity relationship (QSAR) model for some pyrazole/imidazole amide derivatives as mGlu5 inhibitors was developed. The data set was split into the training and test subsets, randomly. The most relevant variables were selected using the genetic algorithm (GA) variable selection method. Multiple linear regression (MLR) method was used as a linear model to predict the activity of mGlu5 inhibitors based on compounds in training set. The external set of nine compounds selected out of 47 compounds, and used to evaluate the predictive ability of QSAR model. The built model could give high statistical quantities (R train 2 = 0.837, Q 2 = 0.759, R test 2 = 0.919) in which proved that the GA-MLR model was a useful tool to predict the inhibitory activity of pyrazole/imidazole amide derivatives. The results suggested that the atomic masses, atomic van der Waals volumes, atomic electronegativities, and the number of imines (aromatic) are the most important independent factors that contribute to the mGlu5 inhibition activity of pyrazole/imidazole amides derivatives.

This work reports the synthesis and characterization of macrocyclic copper(II) complexes encapsulated within the nanopores of zeolite-Y. The obtained nanoparticles entrapped in the nanopores of zeolite have been characterized by FT-IR, UV–Vis, Diffuse reflectance spectra, spectroscopic techniques, molar conductance, magnetic moment data, XRD, thermal, and elemental analysis. The complexes (neat and encapsulated) were used for the oxidation of cyclooctene with tert-butyl hydroperoxide as oxidant in different solvents. The supported Cu[L1]2+-Y exhibited a moderate 81.9% selectivity for epoxidation with 84.2% conversion. The catalytic activity and selectivity of the heterogeneous catalysts do not change after recycling five times.

The quantitative structure-activity relationship (QSAR) of the amino acid derivatives for prediction of histone deacetylase inhibitors activity was studied. Semi-empirical quantum chemical calculations at the AM1 level were used to find the 3D geometry of the studied molecules. The suitable set of the molecular descriptors was calculated, and the important descriptors were selected by the genetic algorithm (GA). The predictive quality of the QSAR model was tested for an external set of eight compounds, randomly chosen out of 38 compounds. The genetic algorithm-multiple linear regression (GA-MLR) model with six selected descriptors was obtained. The accuracy of the proposed GA-MLR model was illustrated using to following evaluation techniques: cross-validation, validation through an external test set, and Y-randomization. This model, demonstrating high statistical qualities .The predictive ability of the model was found to be satisfactory and could be used for predicting the histone deacetylase in...

Use of quantitative structure-activity relation- ships for prediction of the antibacterial activity of pleuromutilin derivatives was studied. A suitable set of molecular descriptors was calculated and the important descriptors were selected by using the variable selections of stepwise multiple linear regression and genetic algo- rithm. Principal-components analysis was used to select the training set. The models were validated by use of leave- one-out (LOO) cross-validation, external test set, and the Y-randomization test. Comparison of the results obtained revealed the superiority of the genetic algorithm over the stepwise multiple regression method for feature selection. One genetic algorithm-multiple linear regression (GA- MLR) model with six selected descriptors was obtained. The root mean square errors of the training and test sets for the GA-MLR model were calculated to be 0.423 and 0.523, and the correlation coefficients were 0.839 and 0.807. The statistical parameter of LOO cross validation test correlation coefficients on the GA-MLR model was 0.760. The predictive ability of the model was satisfactory and it can be used for designing similar groups of anti- bacterial compounds.

In the present study, nano-sized titanium oxides were applied for preconcentration and determination of Pb(II) in aqueous samples using hollow fiber based solid-liquid phase microextraction (HF-SLPME) combined with flame atomic absorption spectrometry (FAAS). In this work, the nanoparticles dispersed in caprylic acid as an extraction solvent was placed into a polypropylene porous hollow fiber segment supported by capillary forces and sonification. This membrane was in direct contact with solutions containing Pb (II). The effect of experimental conditions on the extraction, such as pH, stirring rate, sample volume, and extraction time were optimized. Under the optimal conditions, the performance of the proposed method was investigated for the determination of Pb (II) in food and water samples. The method was linear in the range of 0.6-3000μgmL