STUDIES ON DERIVATIVES OF BAT CHELATES LABELLED WITH ~(67)Ca, ~(113m)In AND ~(201)Tl 1. LABELLING REACTIONS OF BAT DERIVATIVE CHELATES AND BIODISTRIBUTION IN MICE

The use of 3, 3, 10, 10-tetraethyl-1, 2-dithio-5, 8-diazacyclodecane (BAT-TE) and 3, 3, 6, 6, 10, 10-hexamethyl-1, 2-dithio-5, 8-diazacyclodecane(BAT-HM) as new ligands for the preparation of M-BAT-TE(M=Ga~(3+), In~(3+)) and M-BAT-HM(M=Ga~(3+), In~(3+), Tl~(3+)) were investigated. The chelating reactions with high labelling yield are fairly simple and rapid. The biodistribution of BAT derivative chelates in mice exhibited considerable myocardial uptake and good selectivity. Slow washout in heart and high heart-to-blood ratios were observed during the period from 2min to 30min after intravenous injection. Based on these experimental results, M-BAT-TE(M=Ga~(3+), In~(3+)) and M-BAT-HM(M=Ga~(3+), In~(3+), Tl~(3+)) are considered as potential myocardial imaging agents, and particularly Tl-BAT-HM is likely a promising imaging agent.