N,N ',N '',N '''-tetraalkylcyclam derivatives: Synthesis, Tc-99m-labelling, and biological properties

We synthesized N,N ' ,N " ,N ' ' ' -tetraalkylcyclam derivatives in which a lkyl groups were ethyl, propyl, butyl, methoxyethyl, and ethoxyethyl. We at tempted to label the compounds with Tc-99m. The cyclams with methyl, ethyl, and propyl could be labelled. The labelled N,N ' ,N " ,N ' ' ' -tetraalkyl cyclam derivatives showed +1 charge. They excreted rapidly through the kidn ey in mice. The liver-uptake increased slightly as the lipophilicity increa sed. However, the myocardial uptake was low unlikely with the +1 charged my ocardial imaging agents.