Synthesis, Characterization and Bioactivity of Rare Earth Complexes of Thenoylpyrazolone-amino-acid

A new amino-acid Schiff base, 1-phenyl-3-methyl-4-(2-thenoyl) pyrazolone-5-β-alanine (HL) and its ten rare earth complexes have been synthesized. On the basis of elemental analysis and molar conductance, the general formula of the complexes, ·nH2O (RE=La, Nd, Eu, Tb, Y, n=2; RE= Pr, Sm, n=1; RE= Dy, Er, Yb, n=3), is given. They were characterized by IR, UV-visible, 1H NMR, 13C NMR and fluorescence. The results show that the rare earth ions exhibit coordination of eight in the complexes.The antibacterial experiments indicate that they have high antibacterial activities against S. Aureus, B. Subtillis, E. Coli, E. Carotovora and C. Flaccumfaciens.