STUDIES ON THE SYNTHESIS AND RELAXIVITY O F AMINO-ACIDS AND OLIGOPEPTIDES OF GD-DPTA DERIVATIVES

The development of nuclear magnetic resonance imaging technique has pr ovided a noninvasive method for in vivo research in biological systems . Compounds which affect the relaxation time could provides additional contrast for NMR images and are potentially useful in a clinical sett ing. Gd-DTPA is the first MRI contrast agent clinically used, the chel ates of Gd(II) and DTPA derivatives were more selective and less toxic than Gd-DTPA. In this paper, a series of amino acids and oligopeptide s of Gd-DTPA derivatives were synthesized. The structures of these che lates were confirmed by IR and elementary analysis. Toxicity of chelat e was almost the same as Gd-DTPA. The spin-lattice relaxivity (R(1)) o f these chelates was a little bit larger than that of Gd-DTPA.