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This study presents a novel material for highly efficient adsorption of sulforaphane based on SBA-15. The SBA-15 nanoparticles were synthesized using natural silica by hydrothermal method and functionalized with thiol and amine groups by the post-synthesis grafting procedure. All adsorbents were characterized by various techniques including BET, LAXRD, FT-IR, FE-SEM, and CHNS. The batch adsorption experiments revealed that the adsorption efficiency of SBA-15 for sulforaphane can be mainly influenced by the introduction of functional groups and the best adsorption performance was observed for amine-functionalized SBA-15 (SBA-15-NH2) compared to pure SBA-15 and thiol-functionalized SBA-15 (SBA-15-SH) with the highest adsorption efficiency of about 97%. Preliminary adsorption studies of sulforaphane onto SBA-15-NH2 were performed in aqueous solutions with different pH values and various organic solvents. Also, the effects of adsorbent dosage, contact time, and initial sulforaphane concentration on sulforaphane adsorption using SBA-15-NH2 were studied. Langmuir and Redlich-Peterson isotherm models were the best-fitting models for the experimental data, followed by Temkin, Freundlich, and Dubinin-Radushkevich models. The adsorption process could be well described by the pseudo-first-order kinetic model based on kinetic parameters, correlation coefficient, and error functions. Meanwhile, the intra-particle diffusion model showed a multi-linear plot with three steps demonstrating slow diffusion into mesopores as a rate-limiting step.

The sensitivity and reactivity of a B36 borophene were inspected with regard to the drub cisplatinum, in the gas phase and in aqueous solution, applying density functional theory calculations. In the gas phase, the adsorption energy (Ead) was predicted to be −19.6 kcal/mol, and the drug adsorbed via its Cl and H atoms on the edge of the B36 borophene. We found that the B36 electronic properties are meaningfully sensitive to the cisplatinum drug, and so may be a potential sensor for cisplatinum detection. Because of a large HOMO destabilization upon the drug adsorption, the HOMO–LUMO gap (Eg) of the B36 borophene significantly decreased from 1.11 to 0.62 eV, increasing its electrical conductance. A short recovery time of 0.023 s was predicted for desorption of the cisplatinum drug from the B36 borophene surface at room temperature. Unlike the Eg, the Fermi level and work function of the B36 borophene were not changed detectibly by the process of drug adsorption. The adsorption of cisplatinum on the B36 sheet weakens in aqueous solution, and the Ead is −12.3 kcal/mol.

A practical and an efficient Schiff base fluorescent chemosensor, salicylidene-4-aminoantipyrinyl-4-aminophenol (A2) has been synthesized through the condensation procedure of 1-phenyl-2,3-dimethyl-4-(N-2-hydroxybenzylidene)-3-pyrazoline-5-one and 4-aminophenol. Compound A2 has displayed a considerable fluorescence enhancement with high selectivity and sensitivity toward Al3+ ion and exhibited an emission band at 484 nm, which contained a low detection limit (LOD) of 1.06 × 10−7 M. In accordance to the experimental study, DFT, TDDFT calculations, and the enhancement of fluorescence intensity might be attributed to the inhibition of Photoinduced Electron Transfer (PET) along with the Excited-State Intramolecular Proton Transfer (ESIPT). As it has been specified by Job's plot and DFT calculations, the binding stoichiometries of A2 with Al3+ are 1:1, while the association constant (Ka) of Al3+ has been calculated and observed to be 2.67 × × 105 M−1. Furthermore, the binding behavior and sensing mechanism of A2 with Al3+ have been confirmed through the experiments of 1H NMR titration.

An efficient, green, one-pot, and three-component protocol has been reported for the stereoselective synthesis of a new class of spiro thiazolidines. A series of spiro-heterocycle derivatives were produced stereoselectively in high yields by the reaction of 5-arylidene thiazolidine-2,4-diones, isatin, and secondary amino acids in the presence of MnCoCuFe2O4@L-proline (MCCFe2O4@L-proline) magnetic nanorods as a novel nanocatalyst. The synthesized catalyst was fully characterized for thermal stability, magnetic properties, and other physicochemical properties via numerous techniques. It was applied as an efficient and reusable catalyst for the synthesis of endo-isomers of spirocyclic pyrrolidine/pyrrolizidine/pyrrolothiazolidine derivatives in high yield. The regioselectivity and stereochemistry of these heterocyclic spiro-compounds were established by 1H, 13C, HMBC, HSQC, and COSY NMR spectroscopy techniques. The main attractive characteristics of the presented protocol are high yield, high level of diastereoselectivity, and easy recovery of catalyst without significant loss of its catalytic activity.

The highly contagious Coronavirus Disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which is a newborn infectious member of the dangerous beta-coronaviruses (β-CoVs) following SARS and MERS‐CoVs, can be regarded as the most significant issue afflicting the whole world shortly after December 2019. Considering CoVs as RNA viruses with a single-stranded RNA genome (+ssRNA), the critical viral enzyme RNA dependent RNA polymerase (RdRp) is a promising therapeutic target for the potentially fatal infection COVID-19. Nicotinamide riboside (NR), which is a naturally occurring analogue of Niacin (vitamin B3), is expected to have therapeutic effects on COVID-19 due to its super close structural similarity to the proven RdRp inhibitors. Thus, at the first phase of the current molecular docking and dynamics simulation studies, we targeted SARS-CoV-2 RdRp. On the next phase, SARS-CoV RdRp, human Angiotensin-converting enzyme 2, Inosine-5’-monophosphate dehydrogenase, and the SARS-CoV-2 Structural Glycoproteins Spike, Nonstructural viral protein 3-Chymotrypsin-like protease, and Papain-like protease were targeted using the docking simulation to find other possible antiviral effects of NR serendipitously. In the current study, the resulted scores from molecular docking and dynamics simulations as the primary determinative factor as well as the observed reliable binding modes have demonstrated that Nicotinamide Riboside and its active metabolite NMN can target human ACE2 and IMPDH, along with the viral Spro, Mpro, PLpro, and on top of all, RdRp as a potential competitive inhibitor., Graphical Abstract Image, graphical abstract

A novel fluorescent chemosensor calix[4]arene L, containing two fluorogenic coumarin units at the lower rim has been synthesized via click reaction. The structure of this chemosensor, was characterized by IR, NMR spectra and elemental analysis. Ion-binding properties of L were investigated in acetonitrile with different metal ions and the recognition process was monitored by fluorescence, UV-Vis and 1H NMR spectral changes. In comparison with other metal ions, chemosensor L showed a specific selectivity toward copper ions‏. The Job plot analysis revealed that the binding between L with Cu2+ is in 1:1 stoichiometry. The association constant (Ka) for the complex L.Cu2+ was found to be 1.6 × 105 M−1. The limit of detection of the sensor L was determined to be 5.4 × 10−7 M. This sensitive and selective chemosensor was successfully applied for the detection of Cu2+ ions in human blood serum with 90–100% recovery.

A novel Schiff base fluorescent sensor N,N′-bis(salicylidene)-2,6-bis(4-aminophenyl)-4-phenylpyridine (P3) was synthesized through condensation of 2,6-bis(4-aminophenyl)-4-phenylpyridine and 2-hydroxybenzaldehyde. The obtained results from fluorescence analysis revealed that by excess of Cr3+ to P3, a remarkable increase was observed in the fluorescent intensity of the Schiff base at 663 nm with the ratio of CH3CN/H2O (95/5%), even though the other cations would likely have no impact on the fluorescence intensity. The cause of this trend might be ascribed to the formation of a 1:1 stoichiometric P3-Cr3+ complex, confirmed by Job's plot, which is resulted in preventing the photo-induced electron transfer (PET) process. From fluorescence titration, the association constant Ka was gained 2.28 × 105 M−1 and the limit of detection (LOD) was determined to be 1.3 × 10−7 M. Furthermore, the optimized structure together with the electronic spectra of the proposed complex was determined by DFT and TDDFT calculations.

Background: Bioremediation of groundwater and soil contamination is more economical than physicochemical remediation. The present study focused on the bioremediation capability of two bacterial species (Klebsiella planticola and Enterobacter cloacae) from the family Enterobacteriaceae. These bacteria have been identified as new species with capability of degrading methyl tertiary-butyl ether (MTBE). In order to enhance their degradation capability, selected concentrations and retention time were investigated. Methods: The bacteria were cultured on the nutrient agar (NA) medium at room temperature. pH of the medium was adjusted to 7. The medium was autoclaved at 121°C for 15 minutes and incubated for 24 hours at 35°C. After 24 hours, the mixture was inoculated into 50 mL of Luria Bertani (LB) liquid medium containing 50 and 150 ppm MTBE. The cultures were incubated for 2 and 5 days at 35°C and shacked on a shaker at 150 rpm. Cell concentrations of the bacteria in pure culture were determined from the optical density at 600 nm using a UV–VIS spectrophotometer. Then, the culture was centrifuged at 3800 rpm for 20 minutes. In the next step, the MTBE concentration in the supernatant was measured by gas chromatography/mass spectrometry (GC/MS, Agilent Technologies, 5975, US10304411, 5.02.07). Results: The results showed that both strains are able to grow in the presence of 50 and 150 ppm MTBE. In the best conditions, when cell density was 3×108 CFU/mL during 5 days, the highest rate of MTBE degradation for K. planticola and E. cloacae, was 43% and 40%, respectively. It was also revealed that Escherichia coli can degrade 50 and 150 ppm MTBE about 19.8% and 13.65%, respectively. Conclusion: It seems that E. coli can be a good candidate for MTBE degradation at high concentrations for a time longer than that in the present study. It was also found that the species have high performance at 50 ppm than 150 ppm. So, these bacteria can remove MTBE from the environment.

We inspected the possibility of using a synthesized boron nitride nanocluster (B12N12) as a potential chemical sensor for anticancer α-cyano-4-hydroxycinnamic acid (CHC) drug by performing density functional theory calculations. It was found that CHC drug is mainly adsorbed via its acidic group on the BN nanocluster with adsorption energy about − 23.7 kcal/mol. In view of the high decrease of HOMO–LUMO energy gap (Eg) of the BN nanocluster after the adsorption process, it is expected that this process induces a significant increase in its electrical conductivity. Thus, the BN nanocluster is suggested as a potential sensor for CHC drug detection. We predicted that the BN cluster benefits from a short recovery time (~ 22.7 s) and high sensitivity (55.2% decrease in the Eg). Also, it is interesting that the BN nanocluster can be used as a sensor in the pristine form without needing to the functionalization, doping, decoration, etc. Finally, we showed that by increasing the percentage of Hartree–Fock exchange of the functional, the adsorption energy, and sensitivity are increased and decreased, respectively. Also, the sensitivity of the BN nanocluster is predicted to decrease in water solution.

2-((9H-fluoren-2-ylimino) methyl)phenol (F3) was synthesized by condensation reaction of 9H-fluoren-2-amine and 2-hydroxybenzaldehyde in EtOH and characterized by its melting point, 1H-,13C NMR and molecular mass. F3 exhibits a high selectivity for detection of Cr3 + and Al3 + ions as a fluorescent chemosensor and showed a single emission band at 536 nm upon excitation at 333 nm according to fluorescence emission studies. The addition of Cr3 + and Al3 + make a significant increase in fluorescent intensity at 536 nm in CH3CN, while other metal ions have almost no influence on the fluorescence. The fluorescence enhancement was attributed to the inhibited C N isomerization and the obstructed excited state intra-molecular proton transfer (ESIPT) of compound F3. Job's plot and DFT calculations data showed that the binding stoichiometries of F3 with Cr3 + and Al3 + are 2:1. The association constants (Ka) for Cr3 + and Al3 + were calculated and found to be 8.33 × 104 M− 1 and 5.44 × 104 M− 1, respectively. The detection limits were also calculated for Cr3 + and Al3 + and found to be 2.5 × 10− 7 mol/L and 3.1 × 10− 7 mol/L, respectively.

Using density functional theory calculations, we investigated the stability, solubility, structural, electronic, and optical properties of C30X15Y15 (X = B, and Al; Y = N, and P) heterofullerenes. The C30B15N15 is found to be the most stable heterofullerene with standard formation enthalpy (ΔH°f) of 222.2 kcal/mol, followed by C30Al15N15 (ΔH°f = 891.6 kcal/mol). The relative stability of fullerenes are as follows: BN > C60 > AlN ∼ BP > AlP, indicating that the BN doping makes the C60 more stable. The XY doping process significantly increases and decreases the solubility of C60 fullerene in water and benzene solvents, respectively. The standard Gibbs free energy of solvation (ΔG°solv) of C60 in water is increased from −0.7 to −33.5 kcal/mol by AlN doping process. The dopant X atoms are mainly contributed in generation of occupied states but the Y ones largely create the virtual states. Compared to the pristine C60, the electrical conductivity of the XY doped fullerenes are higher, and the order is as follows: AlP > BP > BN ∼ AlN >> C60. This indicates that the Al atoms destabilize and P ones stabilize the HOMO and LUMO levels, respectively. The optical gap of these fullerenes is smaller than the HOMO-LUMO gap by about 0.44–0.55 eV.

Magnetite nanoparticles (MNPs) have proved to be a useful support for heterogeneous catalysis. We have synthesized Fe3O4 MNPs functionalized with a copper(II) complex, and tested the resulting material as a heterogeneous nanocatalyst. The catalyst was tested for aldol condensation reactions between aliphatic/aromatic aldehydes and rhodanine or thiazolidine-2,4-dione (TZD) derivatives under reflux in ethanol, giving the target products in high yield. Environmentally benign chemistry, short reaction times, simple work-up, excellent yields, and the reusability of the new nanocatalyst are beneficial features of the present study. The nanocatalyst was characterized by scanning electron microscopy, vibrating sample magnetometery, thermogravimetry, X-ray diffraction, and energy-dispersive X-ray analyses. The data showed that the magnetic nanoparticles are super-paramagnetic with a size range of 10–20 nm.

Penetration of most of the polar drugs through the cell membrane is a challenging problem. It has been indicated that carbonaceous nanostructures can penetrate into biological cells. Here, we investigated the potential application of a C24 fullerene as a carrier for anti-cancer 5-fluorouracil (5-FU) drug using density functional theory calculations. It was found that the 5-FU interaction with the pristine fullerene is very weak with adsorption energy of about −3.2 kcal/mol which is not suitable for drug delivery. To overcome this problem, one carbon atom is substituted by a boron atom which increases the adsorption energy to −27.2 kcal/mol. The B-doping makes the electronic properties of the fullerene sensitive to the drug. Finally, we proposed a drug release based on the low pH in the cancer cells. It was indicated that attacking protons to the interaction area between the drug and fullerene separates the drug from the carrier.

The adsorption behavior and electronic sensitivity of the pristine, and Al-doped B24N24 (Al-BN) nanoclusters toward two carbonyl halides (F2CO, and Cl2CO (phosgene)) were investigated using density functional calculations. It was found that the carbonyl halides interact with the pristine cluster very weakly while by replacing a B atom of the cluster with an Al atom, the adsorption energy is significantly increased. The electronic properties of the pristine BN nanocluster are not sensitive to F2CO but after the Cl2CO adsorption, its HOMO-LUMO gap (E g) is significantly decreased. Despite this decrease, the BN cage is still insulator and cannot be used as a sensor. The Al-doping overcomes this problem by a primarily reduction in the E g (from 6.45 to 4.88 eV). Our calculations indicate that by F2CO and Cl2CO adsorptions, the Al-BN cluster is transformed from insulator to a semiconductor. This phenomenon largely increases the electrical conductivity of Al-BN and can produce electrical noise which is responsible for the gas detection. Also, it is shown that the Al-BN selectively responses to F2CO and Cl2CO gases.

N , N′ -bis(salicylidene)-2-(6-(2-aminophenyl)-4-phenylpyridin-2-yl) ( 3 ) was synthesized by condensation reaction of 2,6-bis(2-aminophenyl)-4-phenylpyridine and 2-hydroxybenzaldehyde in EtOH and characterized by its melting point, 1 H, 13 C NMR and molecular mass. The addition of Cr 3+ ion makes the significant increase of its fluorescent intensity at 537 nm in CH 3 CN/H 2 O (95/5%), however, other metal ions have almost no influence on the fluorescence. The reason for this phenomenon might be attributed to the formation of a 1:1 stoichiometric 3 -Cr 3+ complex which inhibits photo-induced electron transfer (PET) process. The 1:1 binding stoichiometry between 3 and Cr 3+ was established using Job’s plot, and the complex structure was proposed by DFT calculation. The association constant ( K a ) was determined to be 8.77 × 10 4 M −1 and the limit of detection (LOD) was calculated to be 2.2 × 10 −7 M.

Never agent identification and disposal is vital for both civilian and military defense resources. Herein, using density functional theory calculations, the reactivity and electronic sensitivity of pristine, Stone Wales (SW) defected, and Si-doped BN (Si-BN) nanosheets toward cyclosarin nerve agent were investigated. It was found that the interaction of cyclosarin with the pristine BN sheet is very weak and also that is not energetically favorable with SW defected one. Unlike the SW defect, replacing a B atom by Si atom significantly makes the cyclosarin adsorption energetically favorable. Calculations show that the carbonyl and etheric oxygen atoms of cyclosarin attack the Si atom of Si-BN with the adsorption energies of −73.5 and −136.9 kJ/mol, respectively. The cyclosarin nerve agent can be decomposed by the Si-BN sheet which is thermodynamically highly favorable. Upon this process, the HOMO and LUMO levels are significantly unstabilized and the HOMO-LUMO gap significantly changed by about 24.2%. The cyclosarin presence and its decomposition by Si-BN sheet can be recognized because of the electrical conductivity change of the sheet.

This review article surveys literature methods for the carboxylative cyclization of N -propargylamines with CO 2 to provide 2-oxazolidinones. We have classified these reactions based on the type of catalysts.

Nanographenes are definite segments of graphene whose end atoms are saturated with hydrogens and their properties are different from those of the graphene because of size confinement. Herein, we investigated the structural properties, reactivity and electronic sensitivity of a newly synthesized borazine-like ring doped nanographene (BNG) to NO2 gas by means of density functional theory. We found that the central and peripheral rings of BNG are aromatic, while the middle ones are non-aromatic, revealing that this pattern follows the Clar’s sextet rule of aromaticity. Different thermodynamically stable NO2/BNG complexes are predicted, but most of them cannot be formed at room temperature because of the high transition barrier energies. The most favorable complex is that in which one oxygen atom of NO2 molecule is located above the center of B3N3 doped ring with adsorption energy of about −5.1 kcal/mol. It was found that the electronic properties of BNG are highly sensitive to the presence of NO2 molecules so that after the NO2 adsorption, the BNG is converted from a semiconductor to a semimetal compound. Thus, it was concluded that the BNG may be used in the NO2 sensor devices. Also, a short recovery time is predicted for the NO2 desorption process.

We studied the effect of Hartree-Fock (HF) exchange percentage of a density functional on the adsorption properties and electronic sensitivity of the B 12 N 12 nanocluster to CO molecule. It was found that by an increase in the %HF, the LUMO level is nearly constant while the HOMO level is strongly stabilized, expanding the HOMO-LUMO gap (E g ). Also, the volume of the all structures decreased and the sensitivity of the B 12 N 12 is slightly increased to CO molecule. For the pristine B 12 N 12 cluster, the B66 and B64 bonds are about 1.43 and 1.49 A at 10% HF, and 1.23 and 1.26 A at 100% HF, respectively. The HF exchange between 10–20% may predict an accurate E g for the B 12 N 12 system. We concluded that functionals with a large %HF such as M06-HF, and M06-2X may significantly overestimate the E g , and bond strength. We obtained a parabolic relationship between the %HF and the adsorption energy of CO molecule on the B 12 N 12 cluster. Also, an increase in the %HF predicts a larger charge transfer from the CO molecule to the cage.

Detection of illicit drugs is of increasing interest for police and drug communities because of their abuse. Using density functional calculations, we investigated the interaction of amphetamine (AA) drug with the pristine, B, Al, Ga (group IIIA), Si, and Ge (IIV group) doped C60 fullerenes. The AA cycloaddition from its phenyl ring to the [6–6] bonds of C60 is more favorable than that to the [5–6] bonds, in good agreement with experiment. When an AA molecule is adsorbed from its –NH2 group on the C60 fullerene, its work function is significantly decreased, showing a good sensitivity but the adsorption energy (−0.4 kcal/mol) is very small. Replacing a carbon atom of C60 by the impurity atoms, the interaction between the AA and the C60 is largely improved (adsorption energy ∼ −38.6 to −65.6 kcal/mol). Upon the adsorption of AA on the doped fullerenes, the Fermi level is largely shifted to higher energy, especially in the case of Si and Ge-doped fullerenes, and thus, the work function decreases by about 22.7 and 24.9%, respectively. The electron emission largely increases which can be converted to an electronic noise. However, the Si and Ge-C60 fullerenes are work function-type sensors for AA drug.

We investigated the reactivity and sensitivity of pristine, and Al-doped boron nitride (Al-BN) nanosheets to nerve agents including cyclosarin (GF) and tabun (GA) by means of density functional calculations. A weak interaction is predicted for both GF and GA with the pristine BN sheet with adsorption energies of − 12.0 and − 10.9 kcal/mol, respectively. Calculations show that the carbonyl oxygen atom of both GF and GA are the most nucleophile active site. The electronic sensitivity of the BN nanosheet is predicted to be negligible to these nerve agents. To overcome this problem, we have replaced a B atom of the sheet by an Al atom and investigated the adsorption process. It was found that the reactivity of the sheet in significantly increased to these agents after the Al-doping while the electronic sensitivity is improved only for GA gas. By adsorbing the GA on the Al-BN, its electrical conductivity is largely increased because of a decrease about 32.6% in the HOMO-LUMO energy gap. We have concluded that the Al-doping process helps the BN sheet to detect the GA gas and may be used in its sensor devices.

The electronic, optical, energetic, and structural properties of a HBC (hexa-peri-hexabenzocoronene) nanographene and its central benzene- and coronene-like BN substituted forms, and also full BN analogue were investigated using density functional theory. It was found that a larger number of carbon atoms cause a more negative cohesive energy and, thereby a greater structural stability. Our nucleus independent chemical shift analysis indicates that the aromaticity and Clar’s sextet rule determine the relative stability of these structures. The benzene-like or coronene-like doping makes the HBC more insulator or semiconductor. Electron-hole Frenkel type exciton binding energy was predicted and calculated to be nearly identical for all nanographenes in the range of 0.61–0.69 eV. The coronene-like BN-doped HBC (BN2-HBN) shows higher conductivity due to very narrow optical and HOMO-LUMO energy gap. Partial density of states analysis indicates that the BN2-HBC electronically can be assumed a full BN whose peripheral atoms are replaced by carbon atoms. These carbon atoms are responsible for new states which are appeared within the gap.

Imidazole and its derivatives are privileged N-heterocyclic structures present in various natural products and synthetic pharmaceuticals. Despite the numerous methods that have been developed for the synthesis of imidazole cores, it is still challenging to readily achieve high efficiency and regioselectivity in imidazole synthesis. Therefore, synthesis of these compounds using new protocols is always interesting. In this study we discuss the most representative and interesting reports on the synthesis of imidazoles and their fused analogues from N-propargylamines. Mechanistic aspects of the reactions are considered and discussed in detail.

3-Methyleneindolinone derivatives are important structural motifs found in many compounds of natural occurrence and pharmacological significance. However, despite their wide importance, mild and highly efficient stereoselective synthesis of (E)- and (Z)-3-methyleneindolinones still remains to be a difficult problem. Therefore, the development of new synthetic methods for their stereocontrolled preparation is of prime importance in organic synthesis. In this mini review, we highlight the advances in stereoselective synthesis of mono- and disubstituted-3-methyleneindolinones through metal-catalyzed intramolecular cyclization of N-arylpropiolamides from 1988 to 2017.

The interesting features in the lithium based electride motived us to explore new species with electride properties. To achieve this goal, the tetracyano-2,6-naphthoquinodimethane (TNAP) species has been used as backbone to investigate systematic addition of lithium atoms to the TNAP backbone (Lin@TNAP (n = 1–4) species) through density functional theory (DFT) simulation. After finding the most stable geometries for each Lin@TNAP (n = 1–4) species by full optimization process, we show their electronic-structural features in this work. In the next step, the properties of electron-density-laplacian (∇2ρ(r)), non-linear-optical (NLO), non-nuclear-attractor (NNA), and electron-localization-function (ELF) have been studied to incorporate the reported Lin@TNAP (n = 1–4) species in two different categories, salt or electride. The obtained outcomes present that the Li1@TNAP and the Li2@TNAP molecules are the lithium-salt. In contrast, the Li3@TNAP and the Li4@TNAP molecules are lithium-based electrides along with the isolated electrons in the molecular structure.

Aim and Objective: The magic scaffolds rhodanine and thiazolidine are very important heterocyclic compounds in drug design and discovery. Those are important heterocyclic compounds that have attracted a great deal of attention due to the fact that they exhibit a variety of bioactivities including antibacterial, antifungal, antiviral, antimalarial, and anti-inflammatory activities. These agents often exhibit selective toxicity. The goal of this study was molecular docking, green and solvent-free efficient synthesis of a new series of hetero/aromatic substituted rhodanine and thiazolidine analogues and then investigation of their antimicrobial activity. Materials and Methods: To a mixture of TZD or rhodanine (1 mmol) in the presence of ionic liquid ChCl/urea, various aldehyde (1 mmol) was added. After completion of the reaction, obtained crude compound was collected by filtration and products were recrystallized from ethanol. The binding-free energy between all synthesized compounds with 3EEJ protein (C. glabrata enzyme) were obtained by molecular docking studies. These compounds were evaluated using microdilution method against (ATCC 6538) and (ATCC 12228) Gram-negative, (ATCC 8739) and (ATCC 9027) as Gram-positive and (ATCC 1012), (ATCC 339), C. (ATCC 1057), (ATCC 503), (ATCC 340) and (ATCC 194) as fungi. Results: All of the acceptable products were determined by 1H NMR, 13C NMR, Mas and FT-IR spectroscopy. The binding-free energy between compounds 10a and 10b with 3EEJ protein were found to be -8.08 kcal/mol and -8.15 kcal/mol, respectively. These compounds having a heteroaromatic ring attached to the TZD or rhodanine core showed excellent antimicrobial activity with MIC values of 0.25-8 μg/mL (compound 10a) and 0.5-16 μg/mL (compound 10b) against the most tested fungi strains, Gram-positive and Gram-negative bacteria. Conclusion: A convenient and rapid method has been developed for the synthesis of rhodanine and thiazolidine-2,4-dione (TZD) derivatives as efficient antimicrobial agents using a Deep Eutectic Ionic Liquids (DEILs) choline chloride urea under solvent-free condition. Among the newly synthesized compounds, (Z)-5-((quinoxalin-3-yl) methylene) thiazolidine-2, 4-dione (10a) and (Z)- 5- ((quinoxalin-3-yl) methylene)-2-thioxothiazolidin-one (10b) exerted the promising effect and these compounds can be considered to be further probed as inhibitors of cgDHFR enzyme.

In this work, the interaction of an aspirin (AS) molecule with the external surface of a boron nitride fullerene-like nanocage (B12N12) is studied by means of density functional theory (DFT) calculations. Equilibrium geometry, electronic properties, adsorption energy and thermodynamic stability are identified for all of the adsorbed configurations. Four stable configurations are obtained for the interaction of AS molecule with the B12N12 nanocage, with adsorption energies in the range of −10.1 to −37.7 kcal/mol (at the M06-2X/6-31 + G** level). Our results clearly indicate that Al-doping of the B12N12 tends to increase the adsorption energy and thermodynamic stability of AS molecule over this nanocage. We further study the adsorption of AS over the B12N12 and B11N12Al in the presence of a protic (water) or aprotic (benzene) solvent. It is found that the calculated binding distances and adsorption energies by the PCM and CPCM solvent models are very similar, especially for the B12N12 complexes. According to time-dependent DFT calculations, the Al-doping can shift estimated λ max values toward longer wavelengths (redshift). Solvent effects also have an important influence on the calculated electronic absorption spectra of AS-B12N12 complexes.

Natural phosphate was applied as an efficient and ecofriendly catalyst for the synthesis of tetraketones (2–2.5 h, 90–100 %) and xanthenes (6.5–8.5 h, 84–95 %) via Knoevenagel–Michael cascade reaction of aromatic aldehydes with 1,3-cyclic diketones in water and ethanol, respectively. This protocol provides several advantages over the traditional chemical synthesis, such as simple work-up, easy handling procedure, non-toxicity and stability of catalyst, low cost and environmental friendliness.

This review article is an attempt to survey literature describing synthetic methods in the preparation of quinoline derivatives from N-propargylamines. Mechanistic aspects of the reactions are considered and discussed in detail.

We report an efficient and convenient method for preparing nitro-3-carboxamide coumarin derivatives, proposed as novel fluorescent chemosensor, through microwave irradiation. This compound can be used as fluorescent probe for Cu(2+) with selectivity over other metal ions in aqueous solution. The fluorescence of 6-nitro-N-[2-(dimethylamino)ethyl]-2-oxo-2H-chromene-3-carboxamide(3) is the highest in the presence of Cu(2+), with stronger excitation at λ=320nm than for the other cations tested.

N-Propargylamines are one of the most useful and versatile building blocks in organic synthesis that are successfully transformed into many significant N-heterocycles. Due to high atom economy and shorter synthetic routes, the synthesis of 1,4-oxazepane and 1,4-diazepane cores from N-propargylamines have undergone an explosive growth in recent years. This review gives an overview of new developments in the synthesis of the title compounds from N-propargylamines in recent years. Mechanistic aspects of the reactions are considered and discussed in detail.

The pyridine is one of the simplest, yet most important N-heterocycles. This ring is utilized in more than 100 drugs and this number is increasing by the day. Therefore, synthesis of these compounds using new protocols is always interesting. This review surveys research work on the preparation of pyridines and their ring fused analogues from N-propargylamines. In this review, we have classified these reactions based on the type and the desired products.

Sulforaphane, a promising phytochemical, has received much attention in recent decades as a potential anticarcinogenic compound. In this research work, a novel, specific and affordable method has been developed for the separation and purification of natural sulforaphane from broccoli extract using SBA-15 mesoporous silica. SBA-15 was found to be the most efficient in the purification of sulforaphane compared to some of the conventionally used adsorbents and zeolites. The nanoparticles of SBA-15 mesoporous silica were synthesized using the hydrothermal method from natural amorphous silica extracted from rice husk ash with a silica purity of 96%. Structural and morphological analysis of the synthesized SBA-15 mesoporous silica were performed by the XRD, FT-IR, FE-SEM, and BET techniques. The method includes the primary immiscible solvent extraction of autolyzed broccoli sample with dichloromethane, followed by purification of the extract by SBA-15 mesoporous silica using solid-phase extraction (SPE) method. The recovery of the purified sulforaphane from broccoli extract was >98% using SBA-15 mesoporous silica, which is higher compared to that obtained using current purification methods. The highest purity of sulforaphane product was measured 94% based on the results of analytical HPLC chromatograms. Moreover, the effects of different parameters on the sulforaphane purification by using SBA-15 were studied and optimized.

Exosomes are small extracellular vesicles around 30-100 nm in diameter that are secreted from cells and can be found in most body fluids. Exosomes can be a vital source of biomarkers as they contain various substances (e.g. lipids, RNAs, metabolites and proteins) that can reflect the cell of origin (e.g. cancer cells). For isolation of exosomes present in biological matrices, ultracentrifugation (UC)-based procedures are most common. Other approaches exist, including commercial kits developed for easy and low sample volume isolation. In this study, differential UC and an isolation kit from a major vendor (Total Exosome Isolation Reagent from Thermo Fisher Scientific) were compared. Exosomes were isolated from cell culture media of two different cell sources (patient derived cells from glioblastoma multiforme and the breast cancer cell line MDA-MB-231). For both isolation methods, transmission electron microscopy, dynamic light scattering and western blotting indicated the presence of exosomes. The kit- and UC isolates contained similar amounts of protein measured by the bicinchoninic acid (BCA) assay with absorbance at 562 nm. Using western blot, positive exosome markers were identified in all isolates, and additional exosome markers were identified using MS-based proteomics. For the glioblastoma exosome isolates, the number of proteins identified with liquid chromatography tandem MS (LC-MS/MS) was higher for the UC isolates than the kit isolates when injecting equal protein amounts, contrary to that for the breast cancer exosome isolates. However, negative exosome markers were also found in glioblastoma isolates using LC-MS/MS. Thus, we would not use the term “exosome isolation” as impurities may be present with both isolation methods. Notably, potential biomarkers for both diseases were identified in the isolates using LS-MS/MS. In our opinion, the two isolation methods had rather similar performance, although with some minor differences based on cell of origin.

Aim: For isolation of exosomes, differential ultracentrifugation and an isolation kit from a major vendor were compared. Materials & methods: ‘Case study’ exosomes isolated from patient-derived cells from glioblastoma multiforme and a breast cancer cell line were analyzed. Results: Transmission electron microscopy, dynamic light scattering, western blotting, and so forth, revealed comparable performance. Potential protein biomarkers for both diseases were also identified in the isolates using nanoLC–MS. Western blotting and nanoLC–MS also revealed negative exosome markers regarding both isolation approaches. Conclusion: The two isolation methods had an overall similar performance, but we hesitate to use the term ‘exosome isolation’ as impurities may be present with both isolation methods. NanoLC–MS can detect disease biomarkers in exosomes and is useful for critical assessment of exosome enrichment procedures., Lay abstract Exosomes are small vesicles that are released from biological cells. Exosomes are viewed as being tools for intracellular communication, and there is evidence that cancer cells can release exosomes to, for example, enable metastasis. Exosomes may be very useful for diagnostics, as the detection and characterization of exosomes may allow disease detection at early stages. However, exosomes must be isolated from blood or other biomaterials prior to analysis. This can be a challenging task, and we have here taken a critical look at two familiar isolation techniques, using samples from breast cancer cell lines and brain cancer cells (glioblastoma). We find that the two approaches have comparable performance, and contain protein biomarkers of their cells of origin. However, the isolated exosomes can contain contaminations, which may cloud the analysis in clinical settings. Hence, there is room for new approaches for the isolation of exosomes.

Calculations were performed for investigation of the properties of the electronic structure of Carbon- Doped Boron Phosphide Nanotube (CDBPNT). Pristine and three models of C-doped structures of (6,0) zigzag BPNT were studied at density functional theory (DFT) in combination with 6-311G* basis set using Gaussian package of program. The calculated parameters reveal that various 11 B and 31 P nuclei are divided into some layers with equivalent electrostatic properties. The electronic structure properties are highly influenced by replacement of 11 B and 31 P atoms by 12 C atoms in pristine model. Furthermore, the HOMO−LUMO gap energy for suggested doped models (I), (II) and (III) were lower than pure BPNT pristine systems. The dipole moment values of models (II) and (III) were decreased to 1.788 and 1.789, respectively while the dipole moments of model (I) were enhanced to 4.373, in compare to pure pristine one (2.586). The magnitude of changes in Chemical Shielding (CS) tensor parameters revealed that the electron density at the site of 31 P was higher than that at the site of 11 B due to carbon doping.

We present a systematic investigation of a novel series of star polymers consisting of arms made up from poly(N-isopropylacrylamide)-b-poly(2-acrylamido-2-methylpropanesulfonate) (PNIPAAM-block-PAMPS) block copolymers. The polymers were synthesized as a 3-arm and 2-arm (i.e., a tetrablock copolymer) using a “core-first” method and a sequential atomic transfer radical polymerization (ATRP) protocol. Using asymmetric flow field-flow fractionation (AFFFF), Zetasizer, and small-angle X-ray scattering (SAXS), the phase behavior and nanostructure of the system in dilute solutions are studied in detail. While AFFFF equipped with a light scattering and refractive index detectors provides distribution of molecular weight and overall sizes in solution, we use SAXS combined with theoretical modeling to elucidate the inter- and intramolecular interactions of the star polymers. In particular, by employing a detailed model for a star-diblock copolymer assuming Gaussian chain statistics, we extract the chain conformatio...

In a search for novel antiproliferative agents, a series of quinoxaline derivatives containing 2-aminoimidazole (8a-8x) were designed and synthesized. The structures of synthesized compounds were confirmed by IR, 1H NMR, 13C NMR, Mass Spectroscopy and analyzed using HSQC, COSY, ROESY, HMBC techniques. The anticancer activity of all derivatives were evaluated for colon cancer and breast cancer cell lines by the MTT assay and acridine orange/ethidium bromide double staining method. The anti-cancer effect in human colon cancer (HCT-116) and breast cancer (MCF-7) cell lines exhibited that compounds 8a, 8s, 8t, 8w, 8x appeared as potent antiproliferative agents and especially inhibited the human colon cancer cell proliferation with percentage of inhibition by over 50%. The most active compound was (E)-4-phenyl-1-((quinoxalin-2-ylmethylene)amino)-1H-imidazol-2-amine (8a) with the highest inhibition for MCF-7 (83.3%) and HCT-116 (70%) cell lines after 48 and 24h, respectively. Molecular docking studies of these derivatives within c-kit active site as a validated target might be suggested them as appropriate candidates for further efforts toward more potent anticancer compounds.

With the aim of making specific targeting of silver nanoparticles as a drug for tumor cells and developing new anticancer agents, a novel nano-composite was developed. Albumin coated silver nanoparticles (ASNPs) were synthesized, and their anti-cancerous effects were evaluated against MDA-MB 231, a human breast cancer cell line. The synthesized ASNPs were characterized by spectroscopic methods. The morphological changes of the cells were observed by inverted, florescent microscopy and also by DNA ladder pattern on gel electrophoresis; the results revealed that the cell death process occurred through the apoptosis mechanism. It was found that ASNPs with a size of 90 nm and negatively charged with a zeta-potential of about −20 mV could be specifically taken up by tumor cells. The LD50 of ASNPs against MDA-MB 231 (5 μM), was found to be 30 times higher than that for white normal blood cells (152 μM). The characteristics of the synthesized ASNPs included; intact structure of coated albumin, higher cytotoxicity against cancer cells than over normal cells, and cell death based on apoptosis and reduction of gland tumor sizes in mice. This work indicates that ASNPs could be a good candidate for chemotherapeutic drug.

A series of new N-acetyl/thioacetyl-(E)-stilbene benzenesulfonamide derivatives were synthesized regioselectively in moderate to high yields by following a convenient, three-step procedure. The procedure consists of the direct oxidative conversion of a thiol compound to the corresponding sulfonyl chloride using TMSCl/KNO3, followed by a room temperature reaction in a one-pot transformation of the resultant sulfonyl chloride into N-acetyl/thioacetyl sulfonamide, which undergoes a further Pd-catalyzed coupling reaction, giving rise to the stilbene compounds reported for the first time.

The properties of the electronic structure of the Disiline-doped boron nitride nanotubes (Disiline-BNNTs) are investigated by a density functional theory (DFT) calculation. The structural forms are firstly optimized and the CS tensors calculated. Subsequently, the chemical-shielding isotropic (CSI) and chemical shielding anisotropic (CSA) parameters are found. The shielding values of boron (B) and nitrogen (N) atoms were calculated by Gauge-Including Atomic Orbital (GIAO), Continuous Set of Gauge Transformations (CSGT) and Individual Gauges for Atoms in Molecules (IGAIM) methods, using B3LYP/6-311+G*. The B3LYP level of theory with IGAIM was the best method to evaluate the theoretical chemical shifts for studied models. The results reveal a significant effect of Disiline doping on the chemical shielding tensors at the sites of those 11B and 15N nuclei located in the nearest neighborhood of the Disiline-doped ring. Furthermore, the values of dipole moments and HOMO-LUMO gaps change in the Disiline-doped models in comparison with the original pristine model.

A novel chemiluminescence (CL) method using water-soluble Mn-doped ZnS quantum dots (QDs) as CL emitter is proposed for the chemiluminometric determination of folic acid in pharmaceutical formulation. Water-soluble Mn-doped ZnS QDs were synthesized by using L-cysteine as stabilizer in aqueous solutions. The nanoparticles were structurally and optically characterized by X-ray powder diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), UV-Vis absorption spectroscopy and photoluminescence (PL) emission spectroscopy. The CL of ZnS QDs induced by directly chemical oxidation and its ionic liquid-sensitized effect in aqueous solution were then investigated. It was found that oxidants, especially hydrogen peroxide, could directly oxidize ZnS QDs to produce weak CL emission in basic conditions. In the presence of 1,3-dipropylimidazolium bromide/copper a drastic light emission enhancement is observed, related to a strong interaction between Cu(2+) and the imidazolium ring. Therefore, a new CL analysis system was developed for the determination of folic acid. Under the optimum conditions, there is a good linear relationship between the relative CL intensity and the concentration of folic acid in the range of 1×10(-9)-1×10(-)(6) M of folic acid with a correlation coefficient (R(2)) of 0.9991. The limit of detection of this system was found to be 1×10(-)(10) M. This method is not only simple, sensitive and low cost, but also reliable for practical applications.

A novel chemiluminescence (CL) method using water-soluble Mn-doped ZnS quantum dots (QDs) as sensitizers is proposed for the chemiluminometric determination of atropine in pharmaceutical formulation. Water-soluble Mn-doped ZnS QDs were synthesized by using l -cysteine as stabilizer in aqueous solutions. The nanoparticles were structurally and optically characterized by X-ray powder diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), UV–vis absorption spectroscopy and photoluminescence (PL) emission spectroscopy. It was found that ZnS quantum dots acted as enhancers of the weak CL emission produced upon oxidation of sulfite by Ce(IV) in acidic medium. Trace amounts of atropine improved the sensitize effect of ZnS quantum dots yielding a significant chemiluminescence enhancement of the Ce(IV)–SO 3 2− –ZnS QD system. Therefore, a new CL analysis system was developed for the determination of atropine. Under the optimum conditions, there is a good linear relationship between the relative chemiluminescence intensity and the concentration of atropine in the range of 1×10 −9 –1×10 −6 M of atropine with a correlation coefficient ( R 2 ) of 0.9992. The limit of detection of this system was found to be 2.54×10 −10 M. This method is not only simple, sensitive and low cost, but also reliable for practical applications.

Nanographenes (NGs) are a segment of graphene whose dangling bonds are saturated with hydrogen atoms, introducing different properties and promising applications. Here we investigate the electronic, thermodynamic, optical, and structural properties of four C36X3Y3H18 NGs (X=B, and Al; and Y=N, and P) based on the density functional theory calculations. It was mainly found that 1) BN-NG is planar molecule and the others are buckybowl-shaped ones, 2) The bowl-to-bowl inversion Gibbs free energies (ΔG#) of buckybowl shaped NGs are very huge and the rate constant is very small, hindering the inversion, 3) The relative energetic stability order based on the standard enthalpy of formation (ΔHf°) is as BN>AlN>BP>AlP, which the BN, and AlN doped NGs are stable at room temperature but the BP and AlP doped ones are instable, 4) The electrical conductivity order of magnitude is inverse of that of stability, 5) An exciton binding energy is predicted in the range of 0.57-0.75eV for the NGs which corresponds to Frenkel exciton type, 6) the NGs are not soluble in organic solvent in agreement with the experimental results and is partially soluble in water solvent with Gibbs free energy of solvation (ΔGsolv) in the range of -6.1 to -10.1kcal/mol.