Heterocyclic base adducts of copper (II) complexes have been synthesized by the reaction of copper (II) chloride with 5-chloro-2-hydroxy acetophenone N(4) methyl thiosemicarbazone in presence of heterocyclic base like pyridine (py), 2,2’-bipyridine (bipy), 1,10-phenanthroline (Phen), α/β-picoline. Thiosemcarbazone has been characterized by 13C, 1H NMR as well as IR, electronic spectra. The magnetic and spectroscopic data indicate a square planner geometry for the four coordinate and a distorted square pyramidal for five coordinate complexes. The thiosemicarbazone and its copper (II) complexes show growth inhibitory activity against Pseudomonas Putida, Escherichia Coli, Aspergillus Niger and Candida Albicans. Thiosemicarbazone and its copper (II) complexes have been found antioxidant.