Silver(I), palladium(II), platinum(II) and platinum (IV) complexes with isoorotate and 2-thioisoorotate ligands: synthesis,i.r. and n.m.r. spectra,thermal behaviour and antimicrobial activity

Summary From the reaction of isoorotic and 2-thioisoorotic acids with Ag^I, Pd^II, Pt^II and Pt^IV ions, twelve new complexes containing the uracil ligand in either monoor dianionic forms have been isolated and studied by conductivity measurements, i.r. and n.m.r. spectroscopies, and by thermal methods (t.g. and d.s.c.). From the data obtained, tentative molecular structures are suggested for each complex. The most common coordination mode of both acids involves formation of a six-membered chelate ring through the exocyclic O(4) atom and an oxygen of the carboxylate group. The antimicrobial activity of these compounds against several bacteria and yeast has also been assayed. It is noticeable that PdCl(H₂CU)py complex is active againstPseudomonas sp. andMicrococcus sp. at MIC values lower than 50 g cm^–3.