Technetium labeling of bi, tri and tetradentate ligands derived from 2-aminocyclopentene-1-dithiocarboxylic acid: Characterization and biodistribution of their oxo and nitrido 99mtechnetium complexes

• Published in: Nuclear medicine and biology Vol. 23; no. 3; pp. 353 - 357
• Main Authors: Belhadj-Tahar, H., Coulais, Y., Cros, G., Darbieu, M.H., Tafani, J.A.M., Fabre, J., Esquerré, J.P., Guiraud, R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.04.1996; Elsevier
• Subjects: 2-Aminocyclopentene-1-dithiocarboxylic acid; Aminothiol; Animals; Biodistribution; Biological and medical sciences; Complexes; Contrast media. Radiopharmaceuticals; Isotope Labeling - methods; Ligands; Magnetic Resonance Spectroscopy; Male; Medical sciences; Molecular Structure; Nitridotechnetium; Pharmacology. Drug treatments; Rats; Rats, Wistar; Structure-Activity Relationship; Technetium - pharmacokinetics; Technetium-99m; Thiones - chemical synthesis; Thiones - chemistry; Thiones - pharmacokinetics; Tissue Distribution; X-Ray Diffraction; Nitridotechnetium; 2-Aminocyclopentene-1-dithiocarboxylic acid; Aminothiol; Complexes; Biodistribution; Technetium-99m; Radiolabelling; Dithiocarboxylic acid; Ligand; Radiochemistry; Technetium; Bioavailability; Experimental study; Pharmacokinetics; Chemical synthesis; Chromatography; Comparative study
• ISSN: 0969-8051; 1872-9614
• DOI: 10.1016/0969-8051(95)02100-0

We have synthesized and characterized seven ligands derived from 2-aminocyclopentene-1-dithiocarboxylic acid with different donor sets (SN 2−, SNO 2−, SNN 2−, SNNO 3− and SNNN 3−) and different substituents on the sulfur moieties -SR (with R = H, CH 3 or C 2H 5O(CH 3)CH). With five of these ligands technetium nitrido complexes have been obtained with high yields (over 95%) using rather harsh conditions (pH ≈ 1, temperature ≥ 80 °C), whereas for technetium oxo complexes similar high yields were only obtained with two ligands but with mild conditions (pH = 7–8, temperature ≈ 50 °C). Changing an OH group for an NH 2 has a drastic effect upon labeling yields. The possibility of complexing ligands as either oxo (TcO) 3+ or nitrido (TcN) 2+ derivatives increases the number of available labeled agents with different overall change and consequently with different biological behavior.