Metal-Oxicam Coordination Compounds: Structure, Biological Activity and Strategies for Administration

The crystal structures for metal-oxicam compounds published since the year 2000 are listed and commented in this review. The structural properties are interpreted in order to look for characteristics that might be significant for possible biological activities, for innovative strategies aimed to administering the metal based drugs in vivo. The relevant biological studies are also listed and commented. The number of structural reports on metal-oxicam compounds that were published up to the year 2000 was five, whereas the number of X-ray structures for the same class of compounds published since then is fifteen. The efforts carried out on the field during the past decade increased much and involved several research groups all over the world. The predominant metal was Cu, but interest on Sn increased too, whereas the interest on Pt continued for compounds derived from Zeise’s salt. Other metals linked to oxicam ligands were investigated. The X-ray structural studies until ca ten years ago involved metal-piroxicam compounds, only; instead, during these past ten years also metal-meloxicam, -tenoxicam, -isoxicam, and -lornoxicam were studied and reported. The reactivity of cinnoxicam with copper(II)-acetate was also studied and reported. The coordination arrangement around Cu showed a variety of modes that include pseudo-octahedral, -square planar, -square pyramidal. The oxicam coordination mode depends on the ligand, the reaction media and experimental conditions. The ligands usually occupy the equatorial positions of the coordination sphere and assume ZZZ conformations in the case they are in the anionic form (HOXI).