Group 11 Metal Compounds with Tripodal Bis(imidazole) Thioether Ligands. Applications as Catalysts in the Oxidation of Alkenes and as Antimicrobial Agents
| Autor: | María Contel, Eunmi Hwang, Armando Varela-Ramirez, Renato J. Aguilera, Reema Anis, Rafael Ovalle, Fangwei Liu |
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| Rok vydání: | 2011 |
| Předmět: |
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Molecular tripodal bis(imidazol) thioether pincer ligands Pharmaceutical Science Crystal structure Ligands 01 natural sciences Medicinal chemistry Analytical Chemistry chemistry.chemical_compound Anti-Infective Agents Coordination Complexes Drug Discovery Imidazole Cell Death Imidazoles Chemistry (miscellaneous) visual_art visual_art.visual_art_medium Molecular Medicine group 11 metals Oxidation-Reduction non-toxic Stereochemistry Microbial Sensitivity Tests Alkenes Sulfides 010402 general chemistry Catalysis Article Metal lcsh:QD241-441 Inhibitory Concentration 50 Thioether lcsh:Organic chemistry oxidation alkenes Animals Humans Physical and Theoretical Chemistry Pincer ligand ripodal bis(imidazol) thioether pincer ligands antimicrobial Bacteria 010405 organic chemistry Ligand Organic Chemistry Center (category theory) Fungi 0104 chemical sciences Mice Inbred C57BL chemistry HeLa Cells |
| Zdroj: | Molecules (Basel, Switzerland) Molecules, Vol 16, Iss 8, Pp 6701-6720 (2011) Molecules; Volume 16; Issue 8; Pages: 6701-6720 |
| ISSN: | 1420-3049 |
| Popis: | New group 11 metal complexes have been prepared using the previously described tripodal bis(imidazole) thioether ligand (N-methyl-4,5-diphenyl-2-imidazolyl)2C(OMe)C(CH3)2S(tert-Bu) ({BITOMe,StBu}, 2). The pincer ligand offers a N2S donor atom set that can be used to coordinate the group 11 metals in different oxidation states [AuI, AuIII, AgI, CuI and CuII]. Thus the new compounds [Au{BITOMe,StBu}Cl][AuCl4]2 (3), [Au{BITOMe,StBu}Cl] (4), [Ag{BITOMe,StBu}X] (X = OSO2CF3 − 5, PF6 − 6) and [Cu{BITOMe,StBu}Cl2] (7) have been synthesized from reaction of 2 with the appropriate metal precursors, and characterized in solution. While attempting characterization in the solid state of 3, single crystals of the neutral dinuclear mixed AuIII-AuI species [Au2{BITOMe,S}Cl3] (8) were obtained and its crystal structure was determined by X-ray diffraction studies. The structure shows a AuIII center coordinated to the pincer ligand through one N and the S atom. The soft AuI center coordinates to the ligand through the same S atom that has lost the tert-butyl group, thus becoming a thiolate ligand. The short distance between the AuI–AuIII atoms (3.383 Å) may indicate a weak metal-metal interaction. Complexes 2–7 and the previously described CuI compound [Cu{BITOMe,StBu}]PF6 (9) have been evaluated in the oxidation of biphenyl ethylene with tert-butyl hydrogen peroxide (TBHP) as the oxidant. Results have shown that the AuI and AgI complexes 4 and 6 (at 10 mol % loading) are the more active catalysts in this oxidative cleavage. The antimicrobial activity of compounds 2–5, 7 and 9 against Gram-positive and Gram-negative bacteria and yeast has also been evaluated. The new gold and silver compounds display moderate to high antibacterial activity, while the copper derivatives are mostly inactive. The gold and silver complexes were also potent against fungi. Their cytotoxic properties have been analyzed in vitro utilizing HeLa human cervical carcinoma cells. The compounds displayed a very low cytotoxicity on this cell line (5 to 10 times lower than cisplatin) and on normal primary cells derived from C57B6 mouse muscle explants, which may make them promising candidates as potential antimicrobial agents and safer catalysts due to low toxicity in human and other mammalian tissues. |
| Databáze: | OpenAIRE |
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