Synthesis, crystal structure and antimicrobial activities of two isomeric gold(I) complexes with nitrogen-containing heterocycle and triphenylphosphine ligands, [Au(L)(PPh3)] (HL = pyrazole and imidazole).
Two isomeric gold(I)-triphenylphosphine complexes with nitrogen-containing heterocycles, [Au(L)(PPh3) (HL = pyrazole (1), imidazole (2)) were isolated as colorless cubic crystals for 1 and colorless plate crystals for 2, respectively. The crystal structures of 1 and 2 were determined by single-crystal X-ray diffraction. These complexes were also fully characterized by complete elemental analyses, thermogravimetric/differential thermal analyses (TG/DTA) and FT-IR in the solid state and by solution NMR (31P, 1H and 13C) spectroscopy and molecular weight measurements in acetone solution. These complexes consisted of a monomeric 2-coordinate AuNP core both in the solid state and in solution. The molecular structures of 1 and 2 were compared with those of related gold(I) complexes, [Au(1,2,3-triz)(PPh3)] (3, Htriz = triazole), [Au(1,2,4-triz)(PPh3)]2 (4) as a dimer through a gold(I)-gold(I) bond in the solid state, and [Au(tetz)(PPh3)] (5, Htetz = tetrazole). Selective and effective antimicrobial activities against two gram-positive bacteria (B. subtilis, S. aureus) and modest activities against one yeast (C. albicans) found in these gold(I) complexes 1-4 are noteworthy, in contrast to poor activities observed in the corresponding silver(I) complexes.
Nomiya
K
K
Department of Materials Science, Faculty of Science, Kanagawa University, Hiratsuka, Japan. nomiya@chem.kanagawa-u.ac.jp
Noguchi
R
R
Ohsawa
K
K
Tsuda
K
K
Oda
M
M
D000900:Anti-Bacterial Agents / Q000737:chemistry; D001419:Bacteria / Q000378:metabolism; D018360:Crystallography, X-Ray; D006046:Gold / Q000737:chemistry / Q000378:metabolism*; D007093:Imidazoles / Q000737:chemistry; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009584:Nitrogen / Q000737:chemistry; D050607:Organogold Compounds; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000494:pharmacology*; D011720:Pyrazoles / Q000737:chemistry; D015003:Yeasts / Q000378:metabolism
D000900:Anti-Bacterial Agents; D007093:Imidazoles; D008024:Ligands; D050607:Organogold Compounds; D009942:Organometallic Compounds; D011720:Pyrazoles; C415340:imidazole(triphenylphosphine)gold(I); C415341:pyrazole(triphenylphosphine)gold(I); D006046:Gold; D009584:Nitrogen