Synthesis and Evaluation of Two New Bifunctional Carboxymethylated Tetraazamacrocyclic Chelating Agents for Protein Labeling with Indium-111

Ruser, G; Ritter, W; Maecke, HR

HERO ID

4935909

Reference Type

Journal Article

Year

1990

HERO ID 4935909
In Press No
Year 1990
Title Synthesis and Evaluation of Two New Bifunctional Carboxymethylated Tetraazamacrocyclic Chelating Agents for Protein Labeling with Indium-111
Authors Ruser, G; Ritter, W; Maecke, HR
Journal Bioconjugate Chemistry
Volume 1
Issue 5
Page Numbers 345-349
Abstract The synthesis of two new N- and C-functionalized tetraazamacrocyclic ligands intended to be covalently linked to biomolecules like monoclonal antibodies and to bind the gamma-emitting isotope indium-111 in a thermodynamically and/or kinetically inert way is described. 12-(p-Nitrobenzyl)-l,4,7,10-tetraazacyclotridecane-1,4,7,10-tetraacetic acid (L1) was synthesized by means of bimolecular cyclization with the appropriate malonic acid diethyl ester and triethylenetetraamine, followed by reduction with diborane and alkylation of the cyclic tetraamine with bromoacetic acid. The corresponding triscarboxymethylated ligand L2 was made by statistical alkylation of the tetraamine. Both ligands fulfill the criteria for antibody labeling using the bifunctional chelate approach, namely fast chelate formation, high radiochemical yield, and high stability under physiological conditions. Surprisingly the hepta-dentate ligand L2 confers higher stability to In(3+) and exhibits faster complex formation than octadentate L1. (13)C NMR spectra in solution indicate that the difference in stability is not due to incomplete coordination of all four carboxylate groups in In-L1.
Doi 10.1021/bc00005a008
Wosid WOS:000206175300008
Is Certified Translation No
Dupe Override No
Is Public Yes