Phthalocyanine-peptide conjugates via palladium-catalyzed cross-coupling reactions.

Phthalocyanines (Pc) were conjugated with peptide moieties to improve their target selectivity for potential use as fluorescence and/or positron emission tomography (PET) probes in medical imaging. Three synthetic methods based on palladium-catalyzed cross-coupling reactions (Sonogashira, Buchwald-Hartwig, and Suzuki-Miyaura) were investigated. Using these methods, a series of peptides monofunctionalized with Pc at the N/C-terminal position or on a phenylalanine side chain was obtained in good yields and characterized.