Synthesis and spectroscopic investigation of 6-amino-5-(2-hydroxy-5-substituephenylazoyl)uracil dyes

In this study, novel 6-aminouracil azo dyes (BM1-BM4) were synthesized preparing by 6-aminouracil with some diazotized amino phenols according to the diazo-coupling method. The chemical structures of BM1-BM4 were characterized using FTIR, Micro Element analysis and 1H,13C NMR spectroscopic techniques. The results show that the chemical structures of BM1-BM4 among the possible tautomers in DMSO are compatible with the hydrazone structure. The effects of acid, base and solvent change on the absorption spectra of the dyes were examined. BM1-BM3 were shown exist in a single tautomeric form in methanol and in acidic media, in more than one tautomeric form in basic media probably shown ionization.