The reaction of L-Cysteine with 2-hydroxy naphthaldehyde and 2-hydroxy benzaldehyde yields novel bidentate ligands (2R,4R)-2-(2-hydroxynaphthalen-1-yl)thiazolidine-4-carboxylic acid (L2) and (2R,4R)-2-(2-hydroxyphenyl)thiazolidine-4-carboxylic acid (L1), respectively, which can be characterised based on spectral and physical data. Synthesis of complexes with the formula ML2.XH2O is done via the reaction of L1 and L2 with Cu(II), Fe(II) and VO(II) in molar ratio of 1:2 pertaining to metal to ligand. Based on mass and UV/visible spectra, IR, flam atomic absorption, magnetic susceptibility as well as thermal analysis of metal complexes, we can conclude that the ligands behave as a bidentate and help to identify proper structure pertaining to complexes. Then, screening of the synthesised compounds is carried out to determine their antibacterial activity against Pseudomonas aeruginosa and Streptococcus epidermis. All compounds showed bio-activeness with iron complexes possessing the highest efficiency. The density functional theory at the B3LYP level of theory was employed to calculate the geometry optimisation pertaining to molecular structure as well as energies of ligands and its associated complexes. The observations of the theoretic calculations were in line with the outcomes of the experiment.