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Electrocatalytic destruction of per- and polyfluoroalkyl substances (PFAS) is an emerging approach for treatment of PFAS-contaminated water. In this study, a systematic ab initio investigation of PFAS adsorption on Ni, a widely used electrocatalyst, was conducted by means of dispersion-corrected Density Functional Theory (DFT) calculations. The objective of this investigation was to elucidate the adsorption characteristics and charge transfer mechanisms of different PFAS molecules on Ni surfaces. PFAS adsorption on three of the most thermodynamically favorable Ni surface facets, namely (001), (110), and (111), was investigated. Additionally, the role of PFAS chain length and functional group was studied by comparing the adsorption characteristics of different PFAS compounds, namely perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorobutanesulfonic acid (PFBS), and perfluorobutanoic acid (PFBA). For each PFAS molecule-Ni surface facet pair, different adsorption configurations were considered. Further calculations were carried out to reveal the effect of solvation, pre-adsorbed atomic hydrogen (H), and surface defects on the adsorption energy. Overall, the results revealed that the adsorption of PFAS on Ni surfaces is energetically favorable, and that the adsorption is primarily driven by the functional groups. The presence of preadsorbed H and the inclusion of solvation produced less exothermic adsorption energies, while surface vacancy defects showed mixed effects on PFAS adsorption. Taken together, the results of this study suggest that Ni is a promising electrocatalyst for PFAS adsorption and destruction, and that proper control for the exposed facets and surface defects could enhance the adsorption stability. [Display omitted] • Ab initio investigation of PFAS adsorption on Ni. • Role of PFAS chain length and functional group was studied. • Results revealed that PFAS adsorption on Ni is driven by the functional groups. • Preadsorbed H and solvation produced less exothermic adsorption. • Surface vacancy defects showed mixed effects on PFAS adsorption. [ABSTRACT FROM AUTHOR]

• Disperse azo dyes based on 4-aminoantipyrine were synthesized and characterized by UV–visible, FT-IR and NMR. • Significantly improved fastness properties of the new disperse dyes for the PET fabrics were observed. • The color strengths (K/S) and dye exhaustion indicate high efficiency of disperse dyes on polyester fiber. • The computational results of absorptions spectra of azo disperse dyes are compared with the experimental ones. Disperse azo dyes are important colorants for dyeing polyester fabrics, but developing optimized disperse azo dyes remains a challenge. This work details the synthesis of seven new disperse azo dyes 3a-g derived from the coupling reaction of 4-aminoantipyrine diazonium salt with various phenolic precursors including phenol (3a), salicylic acid (3b), salicylaldehyde (3c), cresols (3d-f), and resorcinol (3g). The dyes were characterized by spectroscopic techniques. Their UV–visible absorption spectra were studied, revealing bathochromic shifts for 3d-g containing electron-donating methyl and hydroxyl substituents compared to parent dye 3a while dyes 3b-c showed hypsochromic shifts. The impact of acid and base on the absorption spectra indicates azo-hydrazone tautomerism for 3f-g but predominant azo form for 3a-e. The dyes showed excellent dyeing on polyester fabrics with up to 97.86 % dye exhaustion. High wash, light and perspiration fastness was exhibited while fastness to respiration varied. The strongest color yield on polyester was achieved with 3g derived from resorcinol coupler. Density functional theory calculations were performed to elucidate relationships between substituent effects and spectral attributes. Lower energy gaps were computed for 3f-g , consistent with enhanced reactivity. This work expands disperse azo dye precursors while offering fundamental structure-performance insight to guide future design. The potent polyester coloration and good fastness properties warrant ongoing investigation of these dyes. [ABSTRACT FROM AUTHOR]

• Cu(II) and Fe(II) complexes of isatin hydrazone derivative are synthesized and characterized. • Cu-catalyst exhibits little more catalytic potential over that of Fe-catalyst in benzyl alcohol oxidation. • The antimicrobial and anticancer potential of both complexes are examined against some bacterial, fungal and human cancer cells. • Their binding ability to ctDNA is examined via UV–Visible spectroscopy and hydrodynamic measurements. Divalent para-magnetic copper(II) and iron(II) chelates of Schiff base isatin hydrazone derivative are synthesized and characterized, as CuLONOCl and Fe(LONO) 2 , respectively. With different stoichiometric ratios (molar ratios) of 1: 1 and 1: 2 of Cu2+ or Fe2+ ion to the ligand (HLONO), both chelates are prepared with distorted square planar and octahedral structures, respectively. The catalytic action of both CuLONOCl and Fe(LONO) 2 is examined in the homogeneous oxidation benzyl alcohol using H 2 O 2 to benzaldehyde (the selective product). All studied compounds involved in the antimicrobial and anticancer studies and also against the ct DNA. Catalytically, their optimization is progressed within the influence of temperature, time and solvent. CuLONOCl manifests an optimized catalytic atmosphere for the yield percentage of benzaldehyde (92%) at 70°C after 4 h, whereas, Fe(LONO) 2 displays less catalytic action with less yield (88%) after 3 h at 90°C. The variation in their structure and central metal ion assign to understand the difference in their catalytic potentials. The proposed mechanism for the oxygenation process based on electron-oxygen transfer steps. In the biological studies, CuLONOCl displays more action against some common microbes (bacteria and fungi) and cancers growth compared to that of Fe(LONO) 2. The role of M2+ ion in its complex and its geometries illustrate their utility in such biological studies within Tweedy's chelation theory. Their interaction with ct DNA (calf thymus DNA) is aimed to represent the impact of Cu2+ and Fe2+ ions in the complexing agents with the influence of their structures through the changes and shifts of spectroscopic the viscosity investigations. Their interaction with ct DNA is illustrated spectroscopically according to the derived values of the binding constants, K b , and the negative Gibbs' free energy, Δ G b ≠. [Display omitted] [ABSTRACT FROM AUTHOR]

• Two manganese(II) and copper(II) complexes of isatin hydrazone were prepared. • They are effective catalysts in oxidation of sulfides by tert -butyl hydroperoxide. • Their antimicrobial and anticancer activities was examined. • They exhibited high anticancer potentials against some human cancer cells. • Their DNA interaction was highly appreciable within spectral tools and viscosity. Two mononuclear manganese(II) and copper(II) complexes were prepared from the coordination of 3,5-di- tert -butyl isatin hydrazone derivative (HLOEt) with either 2 : 1 or 1 : 1 M ratio for Mn(II) or Cu(II) ion, within octahedral and square planar geometries (Mn(LOEt) 2 and CuLOEt), respectively. The catalytic potential of both M(II)-complexes was evaluated in the oxidation of sulfides, i.e. diphenyl sulfide (DPS) and methylphenyl sulfide (MPS), by tert -butyl hydroperoxide (t BuOOH) in acetonitrile. The chemo- and regio-selectivity of the redox system was determined by formation of mono-oxoproducts, diphenyl sufoxide (DPO) and methylphenyl sulfoxide (MPO), with detection of further products of mainly dioxide-product of diphenyl sufone (DPN) and methylphenyl sulfone (MPN). With Mn(LOEt) 2 , the reaction gave 55 and 54% (ee , 79% of S and 21% of R) yields of DPO and MPO, respectively. The catalytic activity of CuLOEt was slightly more progressed than that of Mn(LOEt) 2 , which awarded 52 and 56% (ee , 83% of S and 17% of R) percentages of DPO and MPO, respectively. The higher catalytic reactivity of CuLOEt catalyst was based on their geometrical structures to facilitate the approach of the oxidant and substrate in the redox systems. Their reactivity was studied against some common strains of bacteria and fungi. Moreover, their bio-potential was explored as anticancer reagents versus some human cancer cell lines. Both M(II)-complexes exhibited high biological action against the microorganism and cancer growth. The effect of M(II) ion in thier complexes was examined through the interaction of with ct DNA (calf thymus DNA). Such interaction was tested spectroscopically and via changes in ct DNA viscosity. The reactivity was measured by the binding constant values (K b = 3.19, 13.85 and 15.39 × 108 mol−1 dm3 for HLOEt, Mn(LOEt) 2 and CuLOEt, respectively), which reflects high interaction with ct DNA. Furthermore, the Gibbs' free energy values supported their high potential against ct NDA, with −1.24, −1.36 and −1.37 kJ mol−1, respectively. Furthermore, HLOEt, CuLOEt and Mn(LOEt) 2 were optimized by DFT/B3LYP method under either of 6-31G* of SDD basis set to estimate the essential physical characteristics. On the other hand, in silico approaches were utilized through online software as Swiss-ADME and Pharmacophore beside the molecular docking program. Pharmacokinetic, drug-likeness and the interaction with iso -enzymes were investigated for CuLOEt complex versus receptor tyrosine kinase (2a91, 2src) and human oestrogen receptor (2iok, 4rj3), as well as, liver cancer cells via 6jxt and (PCSK9) Proprotein Convertase Subtilisin/Kexin type 9 (4nmx, 4ne9). Only the proteins 4nmx and 4ne9 from liver cancer cells were found to be effectively inhibited by CuLOEt complex. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mononuclear Cu and VO-complexes were synthesized and characterized. • VO-complex is little more reactive than Cu-one in 1,2-cyclohexene epoxidation. • As biological agents, both complexes exhibited more inhibiting reactivity compared to free ligand. • Their ct DNA-interaction was studied spectroscopically, and by viscosity-measurements. • The molecular docking investigation studied their interaction with ct DNA, theoretically. Polar mononuclear Cu(II) (CuSSL·H 2 O) and VO(II) (VOSSL·0.5H 2 O) complexes were prepared employing 4-hydroxy-3-((2-(4-methoxybenzoyl)hydrazineylidene)methyl)benzene sodium sulfonate ligand (H 2 SSL) under green conditions. The ligand and its complexes were characterized by various spectroscopic (1H &13C NMR, IR, UV–Visible, and Mass) and analytical tools (elemental analysis (EA), thermogravimetric analysis (TGA), conductivity, and magnetic moments). The ionic sodium sulfonate group enhanced the catalytic potential of the two complexes, as green catalysts, in the epoxidation of 1,2-cyclohexene using H 2 O 2 under homogeneous reaction conditions. Interestingly, complete epoxidation (100% conversion) of 1,2-cyclohexene was observed using water as an environmentally friendly solvent. The high valent ion (V4+) in the VO(II)-catalyst offered better catalytic efficiency than that of the low valent ion (Cu2+) in the Cu(II) catalyst. The new compounds' biological activity was assessed using different microbes (Staphylococcus aureus , Serratia Marcescence , Escherichia coli , Candida albicans, Aspergillus flavus, and Trichophyton rubrum), as well as various cancer cell lines (HepG2, MCF-7, and HCT-116). Additionally, their antioxidant potential was also examined by DPPH radical scavenging and SOD assays. Moreover, the activity of the new reagents was assessed towards ct DNA-interaction by spectrophotometry and viscosity measurements. Both M(II)-complexes offered higher antimicrobial, anticancer, and antioxidant potential compared to that of their free ligand. Conformational and in-silico studies were carried out to support the newly synthesized complexes' catalytic and biological properties. [ABSTRACT FROM AUTHOR]

• VO2+, ZrO2+ and Zn2+-complexes were synthesized from the asymmetrical tetradentate imine ligand. • The catalytic differentiation between VO2+-complex and the new ZrO2+- and Zn2+-complexes was studied in the 1,2-cyclohexene (ep)oxidation. • Various parameters were investigated (temperature, time, solvent, oxidant type and catalyst amount), with theoretical evaluation of the mechanism. • Some cyclic and acyclic alkenes were studied in (ep)oxidation reactions. • The catalytic reactivity VO-, ZrO- and Zn-complexes was tested in the 2-aminothiophene oxidation by H 2 O 2 with detection of the most chemoselectives. Three mononuclear di-valent VO2+, ZrO2+ and Zn2+-complexes (VOL, ZrOL and ZnL, respectively) were prepared from asymmetrical di-basic tetradentate di-imine ligand (6,6′-((1 E ,1′ E)-((4-chloro-1,2-phenylene)bis(azaneylylidene))bis(methaneylylidene))bis(2-ethoxy phenol, H 2 L). To confirm the M-complexes compositions, various spectral tools (FT-IR, EI/M and UV-Vis. spectra), molar conductance, thermal, elemental analysis and pXRD analyses were accomplished. Distorted octahedral geometry was confirmed for ZnL and square pyramidal geometry was elucidated for VOL and ZrOL. Their catalytic efficiency was investigated in the epoxidation of 1,2-cyclohexene by H 2 O 2. They exhibited moderate to excellent catalytic control. The effect of temperature, time, solvent, type of oxidant and amount of catalysts were studied in order to determine the optimal catalytic atmosphere. The catalysts screening for epoxidation of alternative cyclic and acyclic olefins at optimization was reported. The variation of central metal ions from high to low valents (Zr4+, V4+and Zn2+ ions) and their capability for oxidation control their catalytic potential are the most effective aspects in the epoxidation reaction. The catalytic oxidation of 2-aminothiophene within VOL, ZrOL and ZnL, as a first trial, by H 2 O 2 was examined. Also, QSAR parameters and DFT studies were performed to predict the catalytic properties of VOL, ZrOL and ZnL, to assert on chosen application. Effective surface properties of VO(II) complex were promoted for progressing its catalytic activity, which already happened. The catalytic mechanism was supported by the sequenced stability difference between proposed intermediates based on the difference in their recorded formation energy from the DFT study. [Display omitted] [ABSTRACT FROM AUTHOR]

• Isolation and characterization of eight bioactive compounds from brown alga sargassum platycarpum for the first time. • Evaluation of the in vitro anticancer activity against HepG-2 cell line. • Computations of MEP, EHOMO, ELUMO and global properties by DFT methods. • Molecular docking study. • Bioactivity Score, drug-likeness and ADMET studies. Image, graphical abstract Recently, macroalgae or seaweeds serve as a treasure of potential drugs for cancer therapy. The present study investigated the cytotoxic activity of eight compounds isolated from the brown alga Sargassum platycarpum for the first time. These isolates were identified as hexadecanoic acid (1), oleic acid (2), saringosterol (3 and 4 , 1:1 mixture of C-24epimers), β -sitosterol (5), glycoglycerolipid (6), loliolide (7) and Kjellmanianone (8) by spectroscopic techniques. Two epimers of saringosterol, (24- R)-saringosterol (3) and (24- S)-saringosterol (4), were subsequently separated by HPLC. (24- S)-saringosterol (4) and (24- R)-saringosterol (3) exhibited potent cytotoxicity against HepG-2 cells with IC 50 of 0.10±0.00 and 0.11±0.00 µM, respectively with compared to standard 5-Fluorouracil (IC 50 of 0.63±0.28 µM) and other isolates. MEP, E HOMO , E LUMO and global properties of all isolated compounds are computed by DFT methods. Molecular docking study showed that most of the isolated compounds especially compounds 3 and 4 interact strongly with 4PYP with the highest binding energies maintained that the high cytotoxic activity of these compounds against HepG-2 cells in the experimental part. Bioactivity Score, Drug-Likeness and ADMET studies supported the potential biological activities of most isolated compounds especially compounds 3 and 4 and also created attention for developing them to act as good candidates. [ABSTRACT FROM AUTHOR]

Two novel complexes for Zn2+ and VO2+ ions, were prepared from tridentate dibasic chelating Schiff base ligand. 1-((3,5-di- tert -butyl-2-hydroxybenzylidene)amino)naphthalen-2-ol-5‑sodium sulfonate (DSHN), was the ligand used in this study. Alternative spectral tools were applied to elucidate structural composition of new compounds. Also, geometry optimization for all synthesizes was conducted by Gaussian09 program via DFT method, to obtain optimal structures and essential parameters. Moreover, the biochemical behavior for all synthesizes, was explored based on tested reactivity against various microbial strains and cancer cells (HCT-116, MCF-7, and HepG-2). The two complexes exhibited interestingly anti-proliferative potential against human cancer cell lines. The antioxidant behavior of the two complexes was studied by DPPH and SOD assays. Particularly, Zn(II) and VO(II) complexes presented more enhanced antimicrobial and anticancer features compared to the free ligand (DSHN), with superiority for VO(II) complex. The binding nature of two complexes with calf thymus DNA (ct DNA), was examined by various methods as, spectrophotometry, viscosity and gel electrophoresis. Their binding efficiency with ct DNA was proposed to be just intercalation or replacement mode. This in-vitro assay was confirmed by in-silico simulation versus 1cca, 1jnx, 1smp, 2 h80 and 5ajh as the co-crystals for selected pathogen-proteins, which attribute to microbes and cancer cells. Unlabelled Image • Synthesis and characterization of VO(II) and Zn(II) –Schiff base complexes • DNA-binding study was executed by variable techniques for confirmation and crystal surface properties were estimated • In-vitro assays were done to evaluate the biological activity which confirmed by in-silico results. [ABSTRACT FROM AUTHOR]