Design, Synthesis, and Evaluation of Novel Magnetic Nanoparticles Combined with Thiophene Derivatives for the Removal of Cr(VI) from an Aqueous Solution.

Most heavy metals are harmful to human health and the environment, even at extremely low concentrations. In natural waters, they are usually found only in trace amounts. Researchers are paying great attention to nanotechnology and nanomaterials as viable solutions to the problem of water pollution. This research focuses on the synthesis of organic thiophene derivatives that can be used as grafted ligands on the surface of silica-coated iron oxide nanoparticles to remove Cr(VI) chromium ions from water. The Vilsmeier-Haack reaction allows the formation of aldehyde groups in thiophene derivatives, and the resulting products were characterized by the FT-IR, NMR, and GC-MS. Schiff base is used as a binder between organic compounds and nanoparticles by the reaction of aldehyde groups in thiophene derivatives and amine groups on the surface of coated iron oxide nanoparticles. Schiff base functionalized Fe3O4 composites (MNPs@SiO2-SB-THCA) and (MNPs@SiO2-SB-THCTA) were successfully synthesized by homogeneous and heterogeneous methods and characterized by a combination of FT-IR, transmission electron microscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The adsorption studies, kinetic modeling, adsorption isotherms, and thermodynamics of the two materials, MNPs@SiO2-SB-THCA and MNPs@SiO2-SB-THCTA, were investigated for the removal of Cr(VI) from water at room temperature and at 50 mg/L. The high adsorption capacity at pH 6 for MNPs@SiO2-SB-THCTA was 15.53 mg/g, and for MNPs@SiO2-SB-THCA, it was 14.31 mg/g.

Charge Transfer Copper Chelating Complex and Biogenically Synthesized Copper Oxide Nanoparticles Using Salvia officinalis Laves Extract in Comparative Spectrofluorimetric Estimation of Anticancer Dabrafenib.

Cancer is a broad category of disease that can affect virtually any organ or tissue in the body when abnormal cells grow uncontrollably, invade surrounding tissue, and/or spread to other organs. Dabrafenib is indicated for the treatment of adult patients with advanced non-small cell lung cancer. In the present study, two newly developed spectrofluorimetric probes for the detection of the anticancer drug Dabrafenib (DRF) in its authentic and pharmaceutical products using an ecologically synthesized copper oxide nanoparticle (CuONPs) from Salvia officinalis leaf extract and a copper chelate complex are presented. The first system is based on the influence of the particular optical properties of CuONPs on the enhancement of fluorescence detection. The second system, on the other hand, acts through the formation of a copper charge transfer complex. Various spectroscopic and microscopic studies were performed to confirm the environmentally synthesized CuONPs. The fluorescence detections in the two systems were measured at λex 350 and λem of 432 nm. The results showed the linear concentration ranges for the DRF-CuONPs-SDS and DRF-Cu-SDS complexes were determined to be 1.0-500 ng mL- 1 and 1.0-200 ng mL- 1, respectively. FI = 1.8088x + 21.418 (r = 0.9997) and FI = 2.7536x + 163.37 (r = 0.9989) were the regression equations. The lower detection and quantification limits for the aforementioned fluorescent systems were determined to be 0.4 and 0.8 ng mL- 1 and 1.0 ng mL- 1, respectively. The results also showed that intra-day DRF assays using DRF-CuONPs-SDS and DRF-Cu(NO3)2-SDS systems yielded 0.17% and 0.54%, respectively. However, the inter-day assay results for the above systems were 0.27% and 0.65%, respectively. The aforementioned two systems were effectively used in the study of DRF with excellent percent recoveries of 99.66 ± 0.42% and 99.42 ± 0.56%, respectively. Excipients such as magnesium stearate, titanium dioxide, red iron oxide, and silicon dioxide used in pharmaceutical formulations, as well as various common cations, amino acids, and sugars, had no effect on the detection of compound.

Unfunctionalized and Functionalized Multiwalled Carbon Nanotubes/Polyamide Nanocomposites as Selective-Layer Polysulfone Membranes.

Nowadays, reverse osmosis is the most widely utilized strategy in membrane technology due to its continuous improvement. Recent studies have highlighted the importance of the surface characteristics of support layers in thin-film membranes to improve their reverse osmosis performance. In this study, interfacial polymerization was used to generate the membranes by employing polyamide as a selective layer on top of the polysulfone supporting sheet. Different membranes, varying in terms of the concentrations of unfunctionalized and functionalized multiwalled carbon nanotubes (MWCNTs), as well as ethanol, have been fabricated. The efficiency of the membrane has been increased by increasing its permeability towards water with high salt rejection. Different characterization techniques were applied to examine all of the fabricated membranes. PA-EtOH 30% (v/v), as a selective layer on polysulfone sheets to enhance the membrane's salt rejection, was shown to be the most efficient of the suggested membranes, improving the membrane's salt rejection. The water permeability of the polyamide membrane with EtOH 30% (v/v) was 56.18 L/m2 h bar, which was more than twice the average permeability of the polyamide membrane (23.63 L/m2 h bar). The salt rejection was also improved (from 97.73% for NaCl to 99.29% and from 97.39% for MgSO4 to 99.62% in the same condition). The PA-MWCNTs 0.15% membrane, on the other hand, had a reduced surface roughness, higher hydrophobicity, and higher water contact angle readings, according to SEM. These characteristics led to the lowest salt rejection, resulting from the hydrophobic nature of MWCNTs.

Crystallographic and Theoretical Exploration of Weak Hydrogen Bonds in Arylmethyl N'-(adamantan-1-yl)piperidine-1-carbothioimidates and Molecular Docking Analysis.

Crystal structures of two potential chemotherapeutic agents, namely 4-nitrobenzyl N'-(adamantan-1-yl)piperidine-1-carbothioimidate 1 and 4-bromobenzyl N'-(adamantan-1-yl)piperidine-1-carbothioimidate 2, have been analyzed in detail. X-ray analysis reveals that the molecular conformations of these compounds are strikingly different. These two structures are compared with two of their closely related structures. In the related structures, morpholine replaces piperidine. Based on the Hirshfeld surface analysis and two-dimensional (2D) fingerprint plots, we describe the effects of piperidine/morpholine and Br/NO2 groups on the intermolecular interactions. An analysis of the CLP-PIXEL energy provides insight into the energetics of the dimers observed in the title compounds and their related structures. Compound 1 stabilizes with bifurcated C-H···S, C-H···O, and O(lp)···C(π) interactions, whereas compound 2 stabilizes with C-H···N, C-H···Br, and C-H···C interactions. The energy frameworks for the crystal structures of the title compounds reveal differences. The atoms-in-molecules (AIM) analysis was performed to confirm the intermolecular interactions found in the crystal structures of 1 and 2. Additionally, docking analysis suggests that the title compounds bind at the active site of human sphingosine kinase 1, a well-known cancer target.

Synthesis, Antimicrobial, and Anti-Proliferative Activities of Novel 4-(Adamantan-1-yl)-1-arylidene-3-thiosemicarbazides, 4-Arylmethyl N'-(Adamantan-1-yl)piperidine-1-carbothioimidates, and Related Derivatives.

The reaction of 4-(adamantan-1-yl)-3-thiosemicarbazide 3 with various aromatic aldehydes yielded the corresponding thiosemicarbazones 4a-g. 1-Adamantyl isothiocyanate 2 was reacted with 1-methylpiperazine or piperidine to yield the corresponding N-(adamantan-1-yl)carbothioamides 5 and 6, respectively. The latter was reacted with benzyl or substituted benzyl bromides to yield the S-arylmethyl derivatives 7a-c. Attempted cyclization of 1,3-bis(adamantan-1-yl)thiourea 8 with chloroacetic acid via prolonged heating to the corresponding thiazolidin-4-one 9 resulted in desulfurization of 8 to yield its urea analogue 10. The thiazolidin-4-one 9 and its 5-arylidene derivatives 11a,b were obtained via microwave-assisted synthesis. The in vitro antimicrobial activity of the synthesized compounds was evaluated against a panel of Gram-positive and Gram-negative bacteria and yeast-like pathogenic fungus Candida albicans. Compounds 7a-c displayed marked broad spectrum antibacterial activities (minimal inhibitory concentration (MIC), 0.5-32 µg/mL) and compounds 4a and 4g showed good activity against Candida albicans. Nine representative compounds were evaluated for anti-proliferative activity towards three human tumor cell lines. Compounds 7a-c displayed significant generalized anti-proliferative activity against all the tested cell lines with IC50 < 10 µM.

Molecular docking and biological evaluation of some thioxoquinazolin-4(3H)-one derivatives as anticancer, antioxidant and anticonvulsant agents.

BACKGROUND: The quinazoline are an important class of medicinal compounds that possess a number of biological activities like anticancer, anticonvulsant and antioxidant etc. RESULTS: We evaluated the previously synthesized quinazoline derivatives 1-3 for their anticancer activities against three cancer cell lines (HepG2, MCF-7, and HCT-116). Among the tested compounds, quinazolines 1 and 3 were found to be more potent than the standard drug Vinblastine against HepG2 and MCF-7 cell lines. All the tested compounds had less antioxidant activity and did not exhibit any anticonvulsant activity. Also, molecular docking studies were performed to get an insight into the binding modes of the compounds with human cyclin-dependent kinase 2, butyrylcholinesterase enzyme, human gamma-aminobutyric acid receptor. These compounds showed better docking properties with the CDK2 as compared to the other two enzymes. CONCLUSIONS: The overall study showed that thioxoquinazolines are suitable antitumor agents and they should be explored for other biological activities. Modification in the available lot of quinazoline and synthesis of its novel derivatives is essential to explore the potential of this class of compounds. The increase in the threat and with the emergence of drug resistance, it is important to explore and develop more efficacious drugs.

Syntheses and crystal structures of two adamantyl-substituted 1,2,4-triazole-5-thione N-Mannich bases.

In the title N-Mannich bases, 3-(adamantan-1-yl)-4-(4-fluoro-phen-yl)-1-[(4-phenyl-piperazin-1-yl)meth-yl]-4,5-di-hydro-1H-1,2,4-triazole-5-thione (C29H34FN5S) (I), and 3-(adamantan-1-yl)-4-(4-fluoro-phen-yl)-1-{[4-(2-meth-oxyphen-yl)piperazin-1-yl]-meth-yl}-4,5-di-hydro-1H-1,2,4-triazole-5-thione (C30H36FN5OS) (II), fluoro-phenyl, adamantane and piperazine moieties are linked to a planar triazole ring. There is an additional phenyl ring on the piperazine ring in (I) and a meth-oxy-phenyl ring in (II). In compound (I), the fluoro-phenyl and phenyl rings are inclined to the triazole ring by 86.55 (13) and 60.52 (12)°, respectively, and the two aryl rings are inclined to one another by 66.37 (13)°. In compound (II), the corresponding dihedral angles are 83.35 (13), 71.38 (15) and 11.97 (16)°, respectively. The crystal structure of (I) shows pairs of C-H⋯F hydrogen bonds forming inversion dimers, while in the crystal of compound (II), in addition to the C-H⋯F hydrogen bonds that generate chains parallel to the b axis, there are C-H⋯π inter-actions present that link the chains to form layers parallel to the ab plane.

Crystal structure of 3-{[4-(2-meth-oxy-phen-yl)piperazin-1-yl]meth-yl}-5-(thio-phen-2-yl)-1,3,4-oxa-diazole-2(3H)-thione.

The title compound, C18H20N4O2S2, is a new 1,3,4-oxa-diazole and a key pharmacophore of several biologically active agents. It is composed of a meth-yl(thio-phen-2-yl)-1,3,4-oxa-diazole-2(3H)-thione moiety linked to a 2-meth-oxy-phenyl unit via a piperazine ring that has a chair conformation. The thio-phene ring mean plane lies almost in the plane of the oxa-diazole ring, with a dihedral angle of 4.35 (9)°. The 2-meth-oxy-phenyl ring is almost normal to the oxa-diazole ring, with a dihedral angle of 84.17 (10)°. In the crystal, mol-ecules are linked by weak C-H⋯S hydrogen bonds and C-H⋯π inter-actions, forming layers parallel to the bc plane. The layers are linked via weak C-H⋯O hydrogen bonds and slipped parallel π-π inter-actions [inter-centroid distance = 3.6729 (10) Å], forming a three-dimensional structure. The thio-phene ring has an approximate 180° rotational disorder about the bridging C-C bond.

Crystal structures of 4-phenyl-piperazin-1-ium 6-chloro-5-ethyl-2,4-dioxopyrimidin-1-ide and 4-phenyl-piperazin-1-ium 6-chloro-5-isopropyl-2,4-dioxopyrimidin-1-ide.

The title mol-ecular salts, C10H15N2 (+)·C6H6ClN2O2 (-), (I), and C10H15N2 (+)·C7H8ClN2O2 (-), (II), consist of 4-phenyl-piperazin-1-ium cations with a 6-chloro-5-ethyl-2,4-dioxopyrimidin-1-ide anion in (I) and a 6-chloro-5-isopropyl-2,4-dioxopyrimidin-1-ide anion in (II). Salt (I) crystallizes with two independent cations and anions in the asymmetric unit. In the crystal structures of both salts, the ions are linked via N-H⋯O and N-H⋯N hydrogen bonds, forming sheets which are parallel to (100) in (I) and to (001) in (II). In (I), the sheets are linked via C-H⋯Cl hydrogen bonds, forming a three-dimensional framework.

Synthesis, Antimicrobial and Hypoglycemic Activities of Novel N-(1-Adamantyl)carbothioamide Derivatives.

The reaction of 1-adamantyl isothiocyanate 4 with the various cyclic secondary amines yielded the corresponding N-(1-adamantyl)carbothioamides 5a-e, 6, 7, 8a-c and 9. Similarly, the reaction of 4 with piperazine and trans-2,5-dimethylpiperazine in 2:1 molar ratio yielded the corresponding N,N'-bis(1-adamantyl)piperazine-1,4-dicarbothioamides 10a and 10b, respectively. The reaction of N-(1-adamantyl)-4-ethoxycarbonylpiperidine-1-carbothioamide 8c with excess hydrazine hydrate yielded the target carbohydrazide 11, in addition to 4-(1-adamantyl)thiosemicarbazide 12 as a minor product. The reaction of the carbohydrazide 11 with methyl or phenyl isothiocyanate followed by heating in aqueous sodium hydroxide yielded the 1,2,4-triazole analogues 14a and 14b. The reaction of the carbohydrazide 11 with various aromatic aldehydes yielded the corresponding N'-arylideneamino derivatives 15a-g. The compounds 5a-e, 6, 7, 8a-c, 9, 10a, 10b, 14a, 14b and 15a-g were tested for in vitro antimicrobial activity against certain strains of pathogenic Gram-positive and Gram-negative bacteria and the yeast-like fungus Candida albicans. The compounds 5c, 5d, 5e, 6, 7, 10a, 10b, 15a, 15f and 15g showed potent antibacterial activity against one or more of the tested microorganisms. The oral hypoglycemic activity of compounds 5c, 6, 8b, 9, 14a and 15b was determined in streptozotocin (STZ)-induced diabetic rats. Compound 5c produced significant reduction of serum glucose levels, compared to gliclazide.

A route to dicyanomethylene pyridines and substituted benzonitriles utilizing malononitrile dimer as a precursor.

The conditions of the reaction of malononitrile dimer with enaminones and arylidenemalononitrile could be adapted to yield either pyridines or benzene derivatives. A new synthesis of pyrido[1,2-a]pyrimidines from the reaction of malononitrile dimer 1 and 2-phenyl-3-piperidin-1-yl-acrylonitrile (11) is described. Compound 1 condensed with DMFDMA to yield an enaminonitrile that reacted with hydrazine hydrate to yield N',4,6-triamino-2H-pyrazolo[3,4-b]pyridine-5-carboxamidine (17).