Use of fluorous and solid-phase electrophiles as scavengers for excess amine in the preparation of sulfur-35 labelled radioligands

A method for scavenging excess amines in sulfur-35-labeled radioligand preparations using fluorous scavengers has been developed in an effort to simplify the purification. This fluorous scavenging has been shown to be effective at removing excess amines from several [35S]sulfonylation mixtures. In many cases this results in one less semi-preparative HPLC purification, and thus in higher radiochemical yield and time savings. Fluorous scavenging was compared to the use of a solid-phase resin (PS-isocyanate) and determined to be approximately equal with respect to recovery of radioactive product. However, the fluorous scavengers were shown to be more effective than solid-phase resin for removing basic amine components. Copyright © 2005 John Wiley & Sons, Ltd.