title: Synthesis, X-ray structure and antimycobacterial activity of silver complexes with alpha-hydroxycarboxylic acids.
abstract: In this paper, synthesis, characterization and antimycobacterial properties of a new water-soluble complex identified as silver-mandelate are described. Elemental and thermal analyses are consistent with the formula [Ag(C(6)H(5)C(OH)COO)](n). The polymeric structure was determined by single X-ray diffraction and the two-dimensional structure is based on the bis(carboxylate-O,O') dimer [Ag-O, 2.237(3), 2.222(3) Angstrom]. The structure is extended along both the b and c axes through two oxygen atoms of a bidentate alpha-hydroxyl-carboxylate residue [Ag-OH(hydroxyl), 2.477(3) Angstrom; Ag-O(carboxylate), 2.502(3) Angstrom; O-Ag-O, 63.94(9) degrees]. A strong d(10)-d(10) interaction was observed between two silver atoms. The Ag - Ag distance is 2.8307(15) Angstrom. The NMR (13)C spectrum in D(2)O shows that coordination of the ligand to Ag(I) occurs through the carboxylate group in solution. Potentiometric titration shows that only species with a molar metal:ligand ratio of 2:2 are formed in aqueous solution. The mandelate complex and the silver-glycolate, silver-malate and silver-hydrogen-tartarate complexes were tested against three types of mycobacteria, Mycobacterium avium, Mycobacterium tuberculosis and Mycobacterium kansasii, and their minimal inhibitory concentration (MIC) values were determined. The results show that the four complexes are potential candidates for antiseptic or disinfectant drugs for discharged secretions of patients affected with tuberculosis.
authors.affiliation: Laboratório de Bioinorgânica e Cristalografia, Departamento de Química, UFSC, CEP 88040-900 Florianópolis, SC, Brazil. alexandre_cuin@yahoo.com
authors.forename: Alexandre
authors.initials: A
authors.lastname: Cuin
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Massabni
authors.forename: Clarice Q F
authors.initials: CQ
authors.lastname: Leite
authors.forename: Daisy N
authors.initials: DN
authors.lastname: Sato
authors.forename: Ademir
authors.initials: A
authors.lastname: Neves
authors.forename: Bruno
authors.initials: B
authors.lastname: Szpoganicz
authors.forename: Marlon S
authors.initials: MS
authors.lastname: Silva
authors.forename: Adaílton J
authors.initials: AJ
authors.lastname: Bortoluzzi
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D018360:Crystallography, X-Ray; D006880:Hydroxy Acids / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009162:Mycobacterium avium / Q000187:drug effects; D019909:Mycobacterium kansasii / Q000187:drug effects; D009169:Mycobacterium tuberculosis / Q000187:drug effects; D011199:Potentiometry; D012834:Silver / Q000737:chemistry* / Q000494:pharmacology; D013055:Spectrophotometry, Infrared; D013816:Thermodynamics
chemical_list: D000900:Anti-Bacterial Agents; D006880:Hydroxy Acids; D012834:Silver