Oxicams as Bioactive Ligand System in Coordination Complexes and Their Biological Applications
Muhammad Naeem, Adnan Ashraf, Muhammad Imran, Waseeq Ahmad Siddiqui, Gulzar Muhammad, Aimon Saleem, Umer Younas, Faisal Ali, Muhammad Asam Raza, Liviu Mitu
Abstract
Oxicam is a class of non-steroidal anti-inflammatory drugs (NSAIDs) that exhibits structural similarities to the enolic acid of 4-hydroxy-1,2-benzothiazine carboxamides. The oxicam derivatives have the ability to coordinate with different metal ions in a monodentate and bidentate fashion. The choice of ligand and reaction conditions played a key role for the synthesis of desired oxicam-based metal complexes. In this review, oxicam-based Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) transition metal complexes are being discussed. In all these complexes, the oxicams acted as N,O-coordinating chelators and stabilized metal complexes by forming six-membered ring systems. The coordination geometries of the metal complexes are dependent on the oxicam derivatives, co-ligands as well as selected metal ions. The octahedral, square pyramidal, square planar and tetrahedral geometries are concluded with the supported by electronic transitions and magnetic data of the oxicam functionalized metal complexes. The antibacterial, anticancer, and DNA interaction of the oxicam-based metal complexes have also been discussed. The antibacterial and anticancer activities indicated that some metal complexes are more potent as compared to free ligands. The DNA binding studies confirmed that the metal complexes interact with DNA via major grooves.