Efficient methods for the synthesis of 5-(4-[18F]fluorophenyl)-10,15,20-tris(3-methoxyphenyl)porphyrin as a potential imaging agent for tumor

F‐18‐labeled porphyrins, the potential tracing and detecting agents for tumor have been synthesized and characterized by two convenient routes: one is a mixed aldehyde condensation, which involves acid‐catalyzed condensation of pyrrole, m‐anisaldehyde and 4‐[18F]fluorobenzaldehyde. The other is the acid‐catalyzed condensation of tetrapyrrane with 4‐[18F]fluorobenzaldehyde. The synthetic methodologies including solvents, reaction concentrations and catalysts are optimized for radiolabeled porphyrins. The methods also provide the desired product in reasonable radiochemical yield (20–26%) compared with those of cold chemical synthesis (1–3%) and with high radiochemical purity (>95%). The methods described here would be effective and convenient ways to produce radiolabeled porphyrin. Copyright © 2005 John Wiley & Sons, Ltd.