Synthesis, labeling and biodistribution of 99mTc-3-amino-2-quinoxalin-carbonitrile 1,4-dioxide in tumor bearing mice

3-Amino-2-quinoxalincarbonitrile 1,4-dioxide (AQCD) is a quinoxaline derivative, which was synthesized by condensation method. AQCD was labeled with 99mTc with labeling yield above 90% investigated by paper chromatography. 99mTc-AQCD was prepared using stannous chloride as reducing agent at pH 7 and 10 min reaction time. 99mTc-AQCD should be freshly prepared, otherwise the yield significantly decreased after 15 min post labeling. Stability study of 99mTc-AQCD reflected the short time stability of Biodistribution study of 99mTc-AQCD in tumor bearing mice reflected that its uptake in tumor sites in both ascites and solid tumor sites. This uptake of 99mTc-AQCD in tumor sites was sufficient to radioimage the inoculated sites. (author)