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

摘要

Potassium 4-(cyclohexylpiperazin-1-yl)-dithioformate (HPDTF) was synthesized from 1-cyclohexylpiperazine. The corresponding Tc-99m-nitrido asymmetrical heterocomplex [(TcN)-Tc-99m(PNP5)(HPDTF)](+) [PNP5 = bis-(dimethoxypropylphosphinoethyl)ethoxyethylamine] was prepared via the [(TcN)-Tc-99m](2+)(int) 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 60min 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. (c) 2007 Elsevier Ltd. All rights reserved.