Synthesis and evaluation of the Tc-99m-complexes of L-cysteine acetyldiglycine (a hybrid of MAG3 and L,L-EC) and of L-beta-homocysteine acetyldiglycine

L-Cysteine acetyldiglycine (L-CAG2), a hybrid compound of L,L-EC and MAG3, and its L P-homocysteine analogue L-HAG2 were synthesized. After labeling w ith Tc-99m, Tc-99m-L-CAG2 and Tc-99m-L-HAG2 gave two peaks on high performa nce liquid chromatography. Urinary excretion of both isomers of Tc-99m-L-CA G2 and Tc-99m L-HAG2 was slower than for the "parent" complexes Tc-99m MAG3 or (TC)-T-99m-L,L-EC. Isomer B of Tc-99m-L-CAG2 showed pronounced kidney r etention in mice (57% of ID in kidneys at 30 min postinjection), but furthe r evaluation in baboon did not reproduce this phenomenon. NUCL MED BIOL 27; 8:781-789, 2000. (C) 2000 Elsevier Science Inc, All rights reserved.