Synthesis, Labeling, and Biological Evaluation of 2-{[Benzyl(cyanomethyl)amino]methyl}-3-(ethoxycarbonyl)-quinoxaline 1,4-Dioxide in Ascites Bearing Mice

摘要

Quinoxaline 1,4-dioxide derivative, 2-{[benzyl(cyanomethyl)amino]methyl}-3-(ethoxycarbonyl) quinoxaline 1,4-dioxide (Q3D), was synthesized and labeled with radioiodine via direct electrophilic substitution giving labeling yield above 90%. The product was examined by paper electrophoresis. ~(125)I-Q_3D was prepared using Chloramine T as oxidizing agent. ~(125)I-Q_3D was stable for up to 72 h post labeling, in contrast to ~(99m)Tc-AQCD which is stable only for a short time. Biodistribution study of ~(125)I-Q_3D in ascites tumor bearing mice revealed large uptake of the labeled compound in tumor sites. In addition, in vitro incubation of the labeled compound with Ehrlich cells indicated incorporation of these compounds in DNA of tumor cells. This uptake of ~(125)I-Q_3D in DNA of tumor cells may be helpful in tumor diagnosis and therapy.