Registre de correu electrònic: Biologically Active Transition Metal Chelates of Ni(II), Cu(II) and Zn(II) With 2-Aminothiazole-Derived Schiff-bases: Their Synthesis, Characterization and the Role of Anions (NO(3), SO(4)(2-), C(2)O(4)(2-)and CH(3)CO(2-)) on Their Antibacterial Properties