Synthesis of new paramagnetic fatty acids and lipophilic spin labels

摘要

Starting from readily available five-membered cyclic nitrones, paramagnetic analogues of palmitic and hexadec-2E-enoic acids are described with a range of pyrrolidine ring orientations. Herein we report the synthesis of 3,4-disubstituted lipophilic pyrroline nitroxides through a palladium-catalyzed cross-coupling reaction. Lipophilic phosphonium salt and SH-specific labels (methanethiosulfonates and isoselenuronium salts) with allylic and propargylic terminal groups are also described.