[Investigation of protonation and complex formation processes of some new polyamino carboxylic acids]

The medicinal chemistry often needs chemical compound with special properties. The preparation of compounds with special properties generally needs 10-20 steps of preparation and the final product is available in small amount. The characterisation of this kinds of compounds needs special methods and procedures for investigation. This kind of method has been developed and used for characterisation of some new polyaminopolycarboxylic acid derivatives. Protolytic equilibrium of 2,2',2",2'"-[terpyridine-6,6"diyl)bis(methylenenitrilo)]tetrakisacetic acid and 3,5-bis[6'-bis (N,N-bis(carboxymethyl)aminomethyl]-2'-pyridyl)-1H,2, 4-triazole was investigated by pH-metric and spectrophotometric methods. The pK values of the aromatic nitrogen atoms were estimated. Complexation of Eu(III)ion with both ligands are studied by spectrophotometric method. Composition(ML2) and stability of complexes were determined.