F‐18 labelled N , N ‐ bis ‐haloethylamino‐phenylsulfoxides — a new class of compounds for the imaging of hypoxic tissue

Two N , N ‐ bis ‐chloroethylamino‐phenylsulfoxides have been synthesized and radiolabelled with F‐18 via halogen exchange. The radiolabelling of both compounds proceeds smoothly with K[ 18 F]F‐kryptofix 2.2.2 complex at 100 °C in DMSO. Decay‐corrected radiochemical yields were 25–35% for [ 18 F] 12 (SO201) and 35–45% for [ 18 F] 11 (SO101), with an average specific activity of 1.8 Ci/µmol. Both compounds remained 80% intact in plasma over a period of 2 h. In vivo binding in a stroke model indicates that both markers are selectively retained in hypoxic tissue. Copyright © 2006 John Wiley & Sons, Ltd.