RESUMO
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.
Assuntos
Antibacterianos/química , Antibacterianos/síntese química , Hidroxiácidos/química , Hidroxiácidos/síntese química , Prata/química , Antibacterianos/farmacologia , Cristalografia por Raios X , Hidroxiácidos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Mycobacterium avium/efeitos dos fármacos , Mycobacterium kansasii/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Potenciometria , Prata/farmacologia , Espectrofotometria Infravermelho , TermodinâmicaRESUMO
A microorganism (Azotobacter sp.) was isolated from soil samples from the Agronomy Faculty campus and its ability to accumulate poly-beta-hydroxyalkanoate (PHAs) polymers was analyzed. The isolated strain (named No 8) accumulated 8 micrograms PHA/m of culture media as intracytoplasmic granules. The following properties of the strain were analyzed: utilization of different carbon sources, antibiotic resistance, optimal pH and temperature, pigment production, nitrogen fixation, proteolytic activity, acid and hydrogen sulphide production, optimal growth temperature, cyst formation, growth on phenol and sodium fluoride, catalase, pleomorfism and mobility. The synthesized polymer showed valuable properties respect to organic solvents resistance.
Assuntos
Azotobacter/metabolismo , Biopolímeros/biossíntese , Hidroxiácidos/síntese química , Microbiologia do Solo , Argentina , Azotobacter/efeitos dos fármacos , Azotobacter/crescimento & desenvolvimento , Azotobacter/isolamento & purificação , Biodegradação Ambiental , Biopolímeros/química , Carbono/metabolismo , Grânulos Citoplasmáticos/metabolismo , Resistência Microbiana a Medicamentos , Metabolismo Energético , Hidroxiácidos/química , SolubilidadeRESUMO
The anticonvulsant activity of a homologous series of phenyl alcohol amides is described. (+-)-2-Hydroxy-2-phenylbutyramide (1), (+-)-3-hydroxy-3-phenylpentanamide (2) and (+-)-4-hydroxy-4-phenylhexanamide (3) were prepared and tested for their anticonvulsant profile and neurotoxicity. 1, 2 and 3 exhibited a broad profile of anticonvulsant activity and a similar significant activity in the seizures provoked by maximal electroshock, pentetrazol, 4-aminopyridine, bicuculline and thiosemicarbazide, but in the strychnine and picrotoxin tests, the protection was variable. The rotarod ataxia test was used to evaluate their neurotoxicity. In this test 2 possesses the lowest neurotoxicity.