Four new ligands (L1-4H) were synthesized from sulfapyridine with 5-bromosalicylaldehyde (for L1H), 5-nitrosalicylaldehyde (for L2H), 5-bromo-3-methoxysalicylaldehyde (for L3H), 5-nitro-3-methoxysalicylaldehyde (for L4H). Mononuclear complexes with a metal ligand ratio 1:1 were prepared with Cu(II) salts. Their structure were elucidated on the basis of elemental analyses, IR, 1H-NMR and 13C-NMR spectra, electronic spectra, magnetic susceptibility measurements and thermogravimetric analyses(TGA). The synthesized compounds were tested for antimicrobial activity against in vitro antibacterial and antifungal activities by the minimum inhibitory concentration (MIC) method. All of the selected compounds showed strong antimicrobial activity against test microorganisms (32-256 μg/mL). Furthermore, the antioxidant activity of the ligands and theirs complexes was determined by DPPH, metal chelating activity methods in vitro. The obtained IC50 value of the DPPH activity for the L1-Cu complex (1.469±0.024 μM) and that of the metal chelating activity for the L3H ligand (% =
Antimicrobial activity; DPPH; Metal Chelating Activity; Sulfa drug; Coordination compounds.