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Experimental and computational works were carried out on a new type of mesoporous silica. In the experimental section, functionalized hollow mesosilica spheres were prepared via a facile technique and then evaluated using some analytical techniques (FESEM, TEM, L-XRD, FTIR, BET-BJH, and TGA). The obtained results revealed that the synthesized material had hollow structure with a diamino-grafted porous shell. The molecular separation of crystal Violet (CV) and neutral Red (NR) dyes from water were investigated by adsorption process using the synthesized powder. Influence of adsorbent loading was evaluated as adsorption ability and dyes removal efficiency. Also, the obtained modeling results revealed appropriate fitting of data with non-linear Langmuir model. The theoretical studies were employed to study the adsorption and removal mechanism of cationic (CV and NR) and anionic (orange II (OII)) dyes using molecular dynamics calculations. Moreover, the simulation outcomes provided valuable information about quantum chemical properties including the HOMO–LUMO maps, chemical reactivity, global softness (σ) and hardness (η) for silica-linker-water-dyes components.

The present study was conducted to design and develop new complexes and their metal-based nanodrug (registered as Casiopeinas® for cancer) with a low toxicity, high efficiency, and high selectivity. First, complexes ([Cu(TTA)(bpy)2] (1) and [Cu(TTA)2(en)] (2) (TTA = 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione) were synthesized and characterized by X-ray diffraction studies, CHN analysis, conductivity measurements, FT-IR and UV-vis spectroscopy. Second, nanoparticles (NPs) of 3 and 4 with the average size of 63.04 and 85.39 nm were prepared with ultrasound. Scanning electron microscopy patterns of 3 and 4 showed irregular spherical and nanorod particles with spongy surface. Furthermore, the anticancer properties of compounds and nano-compounds were studied in MKN-45 cell line. Then, apoptosis studies were carried out utilizing AO/EB staining methods. Finally, to confirm the in vitro experimental data, the theoretical study was carried out by molecular docking studies. The results of DNA docking ana...

The present paper reports the synthesis of two new sulfa drugs: based Schiff base N-(salicylidene) sulfadiazine = sal-sdzH (1) and N-(salicylidene) sulfathiazole = sal-stzH (2) derived from sulfonamide and substituted salicylaldehyde. These compounds were fully characterized by 1H NMR, UV–Vis and FTIR spectroscopy. The molecular structures of both ligands were determined by single X-ray diffraction studies. The crystal structures of ligand (1) are quite different probably due to using the sulfadiazine sodium salt in the synthesis of these ligands. The crystal structures of ligand (2) are mononuclear and monomeric, while the ligand (1) was found to be multinuclear and polymeric. Finally, the DNA docking analysis revealed that the compounds have interactions with the minor groove through hydrogen bonds bases and the backbone phosphates.

Rahime Eshaghi Malekshah,1 Bahareh Fahimirad,1 Ali Khaleghian2 1Department of Chemistry, College of Science, Semnan University, Semnan, Iran; 2Biochemistry Department, Faculty of Medicine, Semnan University of Medical Sciences, Semnan, IranCorrespondence: Ali KhaleghianDepartment of Biochemistry, Faculty of Medicine, Semnan University of Medical Sciences, 5th Km Damghan Road, P.O. Box 3514533, Semnan 3513138111, IranFax +98 2333654202Email khaleghian.ali@gmail.comIntroduction: Over the past several years, nano-based therapeutics were an effective cancer drug candidate in order to overcome the persistence of deadliest diseases and prevalence of multiple drug resistance (MDR).Methods: The main objective of our program was to design organosilane-modified Fe3O4/SiO2/APTS(∼NH2) core magnetic nanocomposites with functionalized copper-Schiff base complex through the use of (3-aminopropyl)triethoxysilane linker as chemotherapeutics to cancer cells. The nanoparticles were characterized by Fourier transform infrared spectroscopy(FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), TEM, and vibrating sample magnetometer (VSM) techniques. All analyses corroborated the successful synthesis of the nanoparticles. In the second step, all compounds of magnetic nanoparticles were validated as antitumor drugs through the conventional MTT assay against K562 (myelogenous leukemia cancer) and apoptosis study by Annexin V/PI and AO/EB. The molecular dynamic simulations of nanoparticles were further carried out; afterwards, the optimization was performed using MM+, semi-empirical (AM1) and AbInitio (STO-3G), ForciteGemo Opt, Forcite Dynamics, Forcite Energy and CASTEP in Materials studio 2017.Results: The results showed that the anti-cancer activity was barely reduced after modifying the surface of the Fe3O4/SiO2/APTS nanoparticles with 2-hydroxy-3-methoxybenzaldehyde as Schiff base and then Cu(II) complex. The apoptosis study by Annexin V/PI and AO/EB stained cell nuclei was performed that apoptosis percentage of the nanoparticles increased upon increasing the thickness of Fe3O4 shell on the magnetite core. The docking studies of the synthesized compounds were conducted towards the DNA and Topoisomerase II via AutoDock 1.5.6 (The Scripps Research Institute, La Jolla, CA, USA).Conclusion: Results of biology activities and computational modeling demonstrate that nanoparticles were targeted drug delivery system in cancer treatment.Keywords: superparamagnetic, Schiff base, core–shell, MTT assay, apoptosis, molecular docking, computational methods, Topoisomerase II

Two novel mononuclear complexes, [Zn (TTA) (bipy)Cl] (1) and [Zn (TTA) (phen)Cl] (2) (TTA = 4,4,4-Trifluoro-1-(2-furyl)-1,3-butanedione, phen = 1,10-phenanthroline and bipy 2, 2ʹ-bipyridine), were synthesized and fully characterized by elemental analyses, 1H NMR, UV–Vis, FTIR spectroscopy, and conductivity measurements. The crystal structures of these two mono-nuclear zinc (II) complexes were determined by X-ray single-crystal diffraction. The result of X-ray diffraction analyses revealed that both complexes have distorted tetragonal-pyramid structures. In MTT cytotoxicity studies, these Zn (II) complexes exhibited antitumor activity against MCF-7 and MKN-45 cell lines. It was also found that the proliferation rate of MCF-7 and MKN-45 cells decreased after treatment with the above-mentioned complexes. In addition, the apoptosis-inducing activity was assessed by AO/EB (Acridine Orange/Ethidium bromide) staining assay and found that they have the potential to act as effective metal-based anticancer drugs. Finally, the molecular docking studies showed that complex 2 strongly binds through minor groove with DNA by relative binding energy −7.33 kcal mol−1.

Present study focused on the adsorption behavior of two cationic dyes (Neutral Red (NR) and Rhodamine B (RB)) on mesoporous silica (MPS) and amino-functionalized MPS with N1-(3-Trimethoxysilylpropyl) diethylenetriamine linker (TAF/MPS). In order to provide more details about adsorption mechanism of dyes on the adsorbents surface, the molecular dynamics (MD) simulations were employed. A very promising simulation approach for adsorption of NR and RB dyes by functionalized and bare MPS adsorbents were obtained by MD results. The obtained results of quantum chemical calculations confirmed the highest adsorption energy for TAF/MPS-water-RB configurations, while the MPS-water-NR had the lowest adsorption energy. According to the results, functionalization of MPS with amino groups led to improvement in adsorption affinity of both dyes. The Sigma profiles demonstrated higher RB adsorption on both adsorbent while lower HOMO–LUMO energy gap was observed for RB dye compared to NR dye. Based on the energies of the HOMO and LUMO, other quantum chemical descriptors were calculated for different dyes, water and adsorbent configurations. These descriptors include: hardness (η), softness (σ), chemical potential (μ), nucleophilicity (ɛ) and electrophilicity index (ω). It was observed that the chemical reactivity, softness, and polarizability of RB dye were more than that of NR dye. The results of this study provide deeper atomic/molecular understanding into the adsorption mechanism of dye molecules on adsorbent surface which could help to get new insights about interactions of molecules. Moreover, MD simulation can be a very useful approach in term of cost-efficient and time saving for predicting the adsorption behavior of structures.

We studied the facile synthesis, design, simulation, and modeling of novel diamino-functionalized hollow mesosilica spheres (DAF-HMSS) structures to remove Neutral Red (NR) and Crystal Violet (CV) from aqueous media. The synthesized sample was characterized by FESEM, TEM, LXRD, BET-BJH, and FTIR techniques. The adsorption and removal mechanism of these hazardous dyes on DAF-HMSS in the presence of water molecules was studied using molecular dynamics simulation. The equilibrium adsorption capacities of DAF-HMSS were computed via the conductor-like screening models with segmented activity coefficients known as COSMO-SAC. Simulation results of optimization by DMol3 showed that adsorption of CV dye by diamino groups of DAF-HMSS is more active in comparison with NR dye. Reactivity of molecules, chemical hardness (η), global softness, and electrophilicity index (ω) of compounds were assessed using the HOMO–LUMO gap. The Sigma profiles of DAF-HMSS with dyes showed that mesoporous adsorption of CV was more than NR while HOMO–LUMO energy gap of CV dye was less than NR. So, the chemical reactivity, chemical softness, and polarizability of CV dye were more than that of water and NR. Meanwhile, the kinetic stability of NR was more than CV dye. Besides, results of electrophilicity index (ω) exhibited high electrophilicity index of CV dye which indicates high toxicity of this dye.

In this study, the metal complex [ZnL(2-aminopyridine)Br] (I) was synthesized from a metal salt with Schiff base ligand (HL). The synthesized complex (I) was elucidated by using FT-IR, UV–Vis spectroscopy, 1H NMR, and. Moreover, the crystal structure of the complex was determined by X-ray analysis and revealed the complex has a distorted tetrahedral coordination structure. The stimulation revealed the binding pattern of this compound with BNA that the free energy (ΔG) of interaction is −7.73 kcal/mol. Also, free energy (ΔG) of complex (I) with EGFR-TKD, ABL/dasatinib complex and the ABL/imatinib complex was by −6.47, - 5.20 and - 6.60 kcal/mol. Then, the nature of the Zn→L bonds in the complex (I) was analyzed with NBO and EDA analyses. In the next step, ZnO nanoparticles were prepared via combustion synthesis method of the complex (I) at 700 °C for 8 h. Finally, crystallinity, purity, and morphology of the ZnO nanoparticles were characterized by FT-IR, XRD, FESEM, and TEM.

This study was conducted to prepare new complexes and their metal-based nanodrugs in order to reduce the growth of human carcinoma cell lines. For this purpose, an extensive study was performed. First, the mixed-chelate Cu(II) complexes Casiopeínas® ([Cu(TTA)(phen)(C1O4)] 1 and [Cu(TTA)(phen)(N3)Cu(TTA)(phen)H2O] (C1O4)·H2O 2 (TTA = 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione) were synthesized and characterized by X-ray, FT-IR, UV–Vis spectroscopy, conductivity measurements, diffuse reflection spectroscopy and elemental analysis studies. Complexes 1 and 2 exhibited tetragonal pyramidal geometry. In the following, nanoparticles (NPs) of complexes 3 and 4 with the average size of 81 and 33 nm, respectively, were prepared by an ultrasonic process. Scanning Electron Microscope (SEM) images of samples 3 and 4 showed that the morphologies of the obtained materials are rod and sphere, respectively. Furthermore, the cytotoxic activity of complexes and nanoparticles was investigated against MKN-45 cell lines. The cell proliferation was inhibited for all compounds and nanocompounds in a dose-dependent manner 1 > 2 > 3 > 4 on MKN-45 cells. Finally, docking calculations were performed to describe the mode of binding to DNA of these complexes. Docking simulations suggested that the compounds bind in the minor groove and preferentially bind to A-T base pair regions. Both complexes also interacted with DNA through one hydrogen-bond.

Four new mononuclear copper(II) complexes with methyl acetoacetate and benzoylacetone in the presence of 1,10-phenanthroline and 2,2ʹ-bipyridine were synthesized and characterized by elemental analyses, FT-IR, and UV–Vis spectroscopy. The molecular structures of complexes [Cu(MAA)(bpy)(ClO4)] (1a), [Cu(bzac)(bpy)]ClO4 (2a), [Cu(MAA)(phen)(ClO4)] (1b) and [Cu(bzac)(phen)(ClO4)] (2b) were determined by single crystal X-ray diffraction technique. 1a, 1b and 2b are five coordinate with a distorted square pyramidal geometry (SP) and the structure of 2a consists of isolated [Cu(bzac)(bpy)]+ cations and perchlorate counter anions. The electrochemical studies of copper complexes in acetonitrile solution showed that CuII/CuI reduction processes are electrochemically irreversible. Cytotoxic activity of complexes was screened, including an MTT assay against gastric cancer cell line (MKN-45). The four Cu(II) complexes exhibited lethal effects against MKN-45 cell lines and the half maximal inhibitory concentration (IC50) values obtained were much lower in comparison with 5-fluorouracil. In addition, MTT and migration studies revealed that benzoylacetone complexes are more active than complexes of methyl acetoacetate against the MKN-45 cancer cell lines. Docking simulations of Cu(II) complexes on DNA revealed that the most stable adducts with DNA bind in the minor groove. All complexes display a binding specificity to the A/T rich regions.

In the present work, we synthesized three novel Cu(II) and Mn(II) complexes (1–3) of a tridentate Schiff base ligand (H2L1) derived from 2-hydroxy-4methoxybenzaldehyde and 2-amino benzyl alcohol. The Schiff base ligand and its complexes were characterized by FT-IR, UV–Vis and elemental analysis. The molecular structures of products were determined by X‐ray diffraction, which confirmed the formation of bi-nuclear (1), tetra-nuclear (2) and tri-nuclear (3) complexes. In addition, the electrochemical properties of the complexes were examined by means of cyclic voltammetry in tetrahydrofuran, which showed the irreversible processes. Molecular docking studies of the free Schiff base ligand and its complexes were performed with BDNA and Interleukin-6 (PDB ID: 1BNA and 1alu ). The results of docked models showed that ligand and its complexes 1–3 preferentially bind to the minor groove of DNA receptor. In addition, complexes 1–3 exhibit higher binding affinity to Interleukin-6 as compared to ligand and drug of anticancer.