The condensation of 2-hydrazino-4-phenyl thiazole and 3-formyl-2-hydroxyquinoline has led to the synthesis of a new Schiff base (L) and its series of mononuclear Co(II), Ni(II) and Cu(II) complexes have also been synthesized. The synthesized Schiff base and its metal complexes were characterized by elemental analyses, spectral techniques (FT-IR, 1H-NMR, 13C-NMR, GC-MS, ESI-MS, UV-Vis, etc;) and magnetic studies. Elemental analyses reveals the [M(L)2.(H2O)2] stoichiometry, where M= Co(II), Ni(II) and Cu(II); “L”= doubly deprotonated ligand. The synthesized metal complexes are completely soluble in DMF and DMSO. The molar conductivity values indicate that, the metal complexes are non-electrolytic in nature. The newly synthesized compounds are good anti-tuberculosis and cytotoxic agents. They have been screened for in-vitro antibacterial and antifungal activities by MIC method. The DNA cleavage activity is studied by agarose gel electrophoresis method using pBR322 Plasmid DNA.