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The marine ecosystem harbors unique and diverse bioactive compounds that can offer a vast repertoire of molecules with therapeutic properties. In the present study, four different species of red marine seaweeds were analyzed for its phytoconstituents and the potent antioxidant and anti-inflammatory activity of the methanolic extracts were screened and determined. The results revealed that, among the 4 samples, G. corticata, scored a good antioxidant potential by DPPH (67.61 ± 1.23%, IC50 = 577.7 µg) and metal chelation assay (29.40 ± 0.32%, IC50 = 1684 µg). The anti-inflammatory analysis has shown that, H. dialata was found to exhibit maximum inhibition against the albumin denaturation (83.50 ± 0.24%), whereas G. corticata was observed to measure a maximum inhibition in heat-induced hemolysis (60.40 ± 0.46%) and proteinase inhibition assay (83.30 ± 0.18%). An extensive literature survey was carried out for the bioactive compounds in G.corticata; it was examined for drug likeliness by ADME analysis and toxicological parameters. Further, the best selected bioactive compounds were subjected to in silico molecular docking with pro-inflammatory target, cyclooxygenase (COX-2). Hexadecanal and Neophytadiene were reported to obtain the highest binding affinity (−5.3) for COX-2 enzyme. Hence, in silico molecular docking studies had shown that G. corticata was found to possess potential anti-inflammatory activity that can prevent conversion of arachidonic acid to prostaglandins by inhibiting COX-2. In addition, molecular dynamic simulation studies have shown the stability of Hexadecanal-6 COX complex. To conclude, the outcomes of the present study may shed light on the understanding of the usage of bioactive compounds for therapeutic purpose. [ABSTRACT FROM AUTHOR]

Five palladium(II) complexes of substituted salicylaldehydes (X-saloH, X = 4-Et2N (for 1), 3,5-diBr (for 2), 3,5-diCl (for 3), 5-F (for 4) or 4-OMe (for 5)) bearing the general formula [Pd(X-salo)2] were synthesized and structurally characterized. The crystal structure of complex [Pd(4-Et2N-salo)2] was determined by single-crystal X-ray crystallography. The complexes can scavenge 1,1-diphenyl-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and reduce H2O2. They are active against two Gram-positive (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative (Escherichia coli and Xanthomonas campestris) bacterial strains. The complexes interact strongly with calf-thymus DNA via intercalation, as deduced by diverse techniques and via the determination of their binding constants. Complexes interact reversibly with bovine and human serum albumin. Complementary insights into their possible mechanisms of bioactivity at the molecular level were provided by molecular docking calculations, exploring in silico their ability to bind to calf-thymus DNA, Escherichia coli and Staphylococcus aureus DNA-gyrase, 5-lipoxygenase, and membrane transport lipid protein 5-lipoxygenase-activating protein, contributing to the understanding of the role complexes 1–5 can play both as antioxidant and antibacterial agents. Furthermore, in silico predictive tools have been employed to study the chemical reactivity, molecular properties and drug-likeness of the complexes, and also the drug-induced changes of gene expression profile (as protein- and mRNA-based prediction results), the sites of metabolism, the substrate/metabolite specificity, the cytotoxicity for cancer and non-cancer cell lines, the acute rat toxicity, the rodent organ-specific carcinogenicity, the anti-target interaction profiles, the environmental ecotoxicity, and finally the activity spectra profile of the compounds. [ABSTRACT FROM AUTHOR]

Six novel copper(II) complexes with the non–steroidal anti–inflammatory drugs ibuprofen, loxoprofen, fenoprofen and clonixin as ligands were synthesized and characterized by diverse techniques including single–crystal X–ray crystallography. The in vitro scavenging activity of the complexes against 1,1–diphenyl–picrylhydrazyl and 2,2′–azinobis(3–ethylbenzothiazoline–6–sulfonic acid) free radicals and the ability to reduce H 2 O 2 were studied in the context of the antioxidant activity studies. The complexes may interact with calf–thymus DNA via intercalation as revealed by the techniques employed. The affinity of the complexes for bovine and human serum albumins was evaluated by fluorescence emission spectroscopy and the corresponding binding constants were determined. Molecular docking simulations on the crystal structure of calf–thymus DNA, human and bovine serum albumins were also employed in order to study in silico the ability of the studied compounds to bind to these target biomacromolecules, in terms of impairment of DNA and transportation through serum albumins, to explain the observed in vitro activity and to establish a possible mechanism of action. Six copper(II) complexes bearing diverse non-steroidal anti-inflammatory drugs as ligands were synthesized and structurally characterized. In vitro studies and in silico molecular docking calculations showed that the compounds may intercalate to calf-thymus DNA, bind tightly to albumins and present effective antioxidant activity. [Display omitted] • Six copper(II) complexes with non-steroidal anti–inflammatory drugs were characterized. • Intercalation is the most possible interaction mode of complexes with calf-thymus DNA. • The complexes showed noteworthy radical scavenging activity. • The complexes may bind tightly and reversibly to serum albumins. • In silico studies of the interaction of the complexes with biomolecules. [ABSTRACT FROM AUTHOR]

The reaction of the dioxouranium(VI) ion with a series of non-steroidal anti-inflammatory drugs (NSAIDs), namely mefenamic acid, indomethacin, diclofenac, diflunisal and tolfenamic acid, as ligands in the absence or presence of diverse N,N′–donors (1,10–phenanthroline,2,2′–bipyridine or 2,2′–bipyridylamine) as co–ligands led to the formation of ten complexes bearing the formulas [UO 2 (NSAID–O,O′) 2 (O–donor) 2 ] or [UO 2 (NSAID–O,O′) 2 (N,N′–donor)], respectively. The complexes were characterized with diverse spectroscopic techniques and the crystal structures of three complexes were determined by single–crystal X–ray crystallography. The biological profile of the resultant complexes was assessed in vitro and in silico. The in vitro studies include their antioxidant properties (ability to scavenge free radicals 1,1–diphenyl–picrylhydrazyl and 2,2′–azinobis(3–ethylbenzothiazoline–6–sulfonic acid) and to reduce H 2 O 2), their interaction with DNA (linear calf–thymus DNA or supercoiled circular pBR322 plasmid DNA) and their affinity for serum albumins (bovine and human serum albumin). In silico molecular docking calculations were performed regarding the behavior of the complexes towards DNA and their binding to both albumins. Ten novel dioxouranium(VI) complexes bearing non-steroidal anti-inflammatory drugs as ligands were synthesized and structurally characterized. In vitro studies and in silico molecular docking calculations showed that the compounds may intercalate to calf-thymus DNA, cleave plasmid DNA, bind tightly to albumins and present effective antioxidant activity. [Display omitted] • Ten dioxouranium(VI) complexes with non-steroidal anti-inflammatory drugs. • The complexes show promising radical scavenging activity. • The complexes may bind tightly and reversibly to serum albumins. • Intercalation of the complexes with calf-thymus or plasmid DNA. • In silico studies of the interaction of the complexes with biomolecules. [ABSTRACT FROM AUTHOR]

Five novel nickel(II) complexes with the non–steroidal anti–inflammatory drug sodium meclofenamate (Na–mclf) have been synthesized and characterized in the absence or co–existence of the nitrogen–donors imidazole (Himi), 2,2′–bipyridylamine (bipyam), 2,2′–bipyridylketoxime (Hpko) and 2,9–dimethyl–1,10–phenanthroline (neoc); namely [Ni(mclf–O) 2 (Himi) 2 (MeOH) 2 ], [Ni(mclf–O) 2 (MeOH) 4 ], [Ni(mclf–O)(mclf–O,O′)(bipyam)(MeOH)]·0.25MeOH, [Ni(mclf–O,O′) 2 (neoc)] and [Ni(mclf–O) 2 (Hpko–N,N′) 2 ]·MeOH·0.5H 2 O. The affinity of the complexes for calf–thymus (CT) DNA was investigated by various techniques and intercalation is suggested as the most possible interaction mode. The interaction of the complexes for bovine and human serum albumins was also investigated in order to determine the binding constants, concluding that the complexes bind reversibly to albumins for the transportation towards their target cells or tissues and their release upon arrival at biotargets. The antioxidant activity of the compounds was evaluated via their ability to scavenge 1,1–diphenyl–picrylhydrazyl and 2,2′–azinobis(3–ethylbenzothiazoline–6–sulfonic acid) free radicals and to reduce H 2 O 2. For the determination of the anticholinergic ability of the complexes the in vitro inhibitory activity against the enzymes acetylcholinesterase and butyrylcholinesterase was evaluated and presented promising results. The in silico molecular modeling calculations employed provide useful insights for the understanding of the mechanism of action of the studied complexes at a molecular level. This applies on both the impairment of DNA by its binding with the studied complexes and transportation through serum albumins, as well as the ability of these compounds to act as anticholinergic agents. Five nickel(II) complexes with meclofenamato ligands have been synthesized and characterized. The compounds may behave in vitro as DNA-intercalators, reversible albumin-binders, active radical scavengers and good cholinesterase inhibitors. The results were supported by in silico molecular docking calculations. [Display omitted] • Five nickel(II) complexes with meclofenamato ligands were characterized. • In vitro / in silico studies of the biological activity of complexes were performed. • The complexes may bind tightly and reversibly to serum albumins. • Intercalation is the most possible binding mode of complexes to calf-thymus DNA. • Complexes exhibit remarkable inhibitory activity against cholinesterase enzymes. [ABSTRACT FROM AUTHOR]

The interaction of cobalt chloride with the non-steroidal anti-inflammatory drug indomethacin (Hindo) led to the formation of the polymeric complex [Co(indo-O) 2 (H 2 O) 2 (μ-Cl)] n ·n(MeOH·H 2 O) bearing one chlorido bridge between the cobalt atoms. The presence of the nitrogen-donor co-ligands 2,2′-bipyridine (bipy), 2,2′-bipyridylamine (bipyam), 1,10-phenanthroline (phen) or 1 H -imidazole (Himi) resulted in the isolation of complexes [Co 2 (μ-indo-O,O′) 2 (indo-O) 2 (bipy) 2 (μ-H 2 O)]·3.3MeOH, [Co(indo-O,O′) 2 (bipyam)]·0.9MeOH·0.2H 2 O, [Co(indo-O,O′) 2 (phen)] (4) and [Co(indo-O) 2 (Himi) 2 ] (5), respectively, where the indomethacin ligands were coordinated in diverse manners. The study of the affinity of the complexes for calf-thymus DNA revealed their intercalation between the DNA-bases. The binding of the complexes to albumins was also examined and the corresponding binding constants and binding subdomain were determined. The free radical scavenging activity of the compounds was evaluated towards 1,1-diphenyl-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid). Molecular modeling calculations may usually provide a molecular basis for the understanding of both the impairment of DNA by its binding with the studied complexes and the ability of these compounds to transportation through serum albumin proteins. This study can provide information for the elucidation of the mechanism of action of the compounds in a molecular level. Five novel cobalt complexes bearing indomethacin ligands have been synthesized and structurally characterized. The compounds may behave as DNA-intercalators, tight albumin-binders and effective free radical scavengers as shown by in vitro studies and by in silico molecular docking calculations. Unlabelled Image • Five cobalt complexes with indomethacin ligands were characterized. • The complexes show noteworthy radical scavenging activity. • The complexes may bind tightly and reversibly to serum albumins. • Intercalation is the most possible binding mode of the complexes to calf-thymus DNA. • In silico studies of the interaction of the complexes with biomolecules are conducted. [ABSTRACT FROM AUTHOR]