Preparation of 99mTc-nitrido asymmetrical heterocomplex with 4-(cyclohexylpiperazin-1-yl)-dithioformate and its biological evaluation as a potential myocardial imaging agent.

Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, PR China. ljie74@bnu.edu.cn

Potassium 4-(cyclohexylpiperazin-1-yl)-dithioformate (HPDTF) was synthesized from 1-cyclohexylpiperazine. The corresponding (99m)Tc-nitrido asymmetrical heterocomplex [(99m)TcN(PNP5)(HPDTF)](+) [PNP5=bis-(dimethoxypropylphosphinoethyl)ethoxyethylamine] was prepared via the [(99m)TcN](int)(2+) precursor in high yields (>95%) and characterized by HPLC and paper electrophoresis. It was found to be lipophilic and cationic, with high stability in vitro. Studies of its biodistribution in mice showed high heart uptake and good myocardial retention ((11.12+/-1.41)% ID/g at 5 min and (10.88+/-1.45)% ID/g at 120 min), as well as rapid clearance from liver, blood and soft tissues. At 60 min post-injection, the heart-to-liver, heart-to-lung and heart-to-blood ratios were 1.30, 3.89 and 27.56, respectively, which suggested that the complex might be suitable for myocardial imaging.

PMID: 17616466 [PubMed - indexed for MEDLINE]