Six new a-aminonitriles were prepared by treatment of 0-hydroxy benzaldehyde with different aromatic amines including aniline, m-methoxy aniline, paminoacetophenone, p-aminobenzoic acid, p-aminophenol and 0-aminophenol, in the presence of potassium cyanide, and glacial acetic acid as a solvent at pH4.The synthesized a-aminonitriles were characterized by FTIR spectra, C.H.N. analysis and mass spectroscopy. II. Six new coumaran-2-one derivatives were prepared by cyclization of a-aminonitriles through hydrolysis by 10% sulfuric acid in a steam bath for 30 min. the products were characterized by their FTIR spectra, C.H.N. analysis and mass spectroscopy. III. The interaction of the prepared a-aminonitriles with cobalt (II) and copper (II) ions were studied in solution following mole ratio method, the metal:ligand ratio in the formed complexes was found to be 1:3 and 1:2 for Co (II) and Cu(II) respectively. IV. All of the compounds prepared in I and II were screened for their antibacterial activity against two types of selected pathogenic bacteria ( Staph. G+ and E. coli G)