The compound 5-((2-aminoethylamino)methyl)-7-(4-bromoanilino)-3- cyanopyrazolo[ 1,5-a]pyrimidine (ABCPP) was synthesized and conjugated with N-mercaptoacetylglycine (MAG), N-mercaptoacetylphenylalanine (MAF) and N-mercaptoacetylvaline (MAA), respectively. These three compounds were labeled successfully with [99mTcN]2+ intermediate in high radiochemical purities. Biodistribution in tumor-bearing mice demonstrated that the three new complexes showed tumor accumulation, high tumor-tomuscle (T/M) ratios and fast clearance from blood and muscle. Among them, the 99mTcNMAG-ABCPP showed the most favorable characteristics, with tumor/blood and tumor/muscle ratios reaching 1.51 and 2.97 at 30 min post-injection, 1.84 and 2.49 at 60 min post-injection, suggesting it could be further studied as potential tumor imaging agent for single photon emission computed tomography (SPECT). © 2010 by the authors; licensee MDPI, Basel, Switzerland.
Ding, R., He, Y., Xu, J., Liu, H., Wang, X., Feng, M., … Zhang, J. (2010). Synthesis and biological evaluation of pyrazolo[1,5-a]-pyrimidine- containing 99mTc nitrido radiopharmaceuticals as imaging agents for tumors. Molecules, 15(12), 8723–8733. https://doi.org/10.3390/molecules15128723