Synthesis, spectroscopic properties, and antimicrobial activity of some new 5-phenylazo-6-aminouracil-vanadyl complexes

Six complexes, {[}VO(L-1-H)(2)]center dot 5H(2)O (1), {[}VO(OH)(L-2,L-3-H)(H2O)]center dot H2O (2,3), {[}VO(OH) (L-4,L-5-H)(H2O)]center dot H2O (4,5), {[}VO(OH)(L-6-H)(H2O)]center dot H2O (6), were prepared by reacting different derivatives of 5-phenylazo-6-aminouracil ligands with VOSO4 center dot 5H(2)O. The infrared and H-1 NMR spectra of the complexes have been assigned. Thermogravimetric analyses (TG, DTG) were also carried out. The data agree quite well with the proposed structures and show that the complexes were finally decomposed to the corresponding divanadium pentoxide. The ligands and their vanadyl complexes were screened for antimicrobial activities by the agarwell diffusion technique using DMSO as solvent. The minimum inhibitory concentration (MIC) values for 1-4 and 6 were calculated at 30 degrees C for 24-48 h. The activity data show that the complexes are more potent antimicrobials than the parent ligands.