Synthesis of porphyrin alpha,omega-bis(methylamino)peptide constructs

New monofunctionalised electrophilic and nucleophilic derivatives of 5,10,1 5,20-tetraphenyl-21H,23H-porphine (TPP) have been developed for controlled attachment to peptide amino and carboxyl side-chains, respectively. Reactio n of 5-(4-aminophenyl)-10,15,20-triphenyl-21H,23H-porphine with 4-nitrophen yl chloroformate gave the corresponding nitrophenyl carbamate which coupled efficiently to lysine epsilon-amines. The aminophenylporphyrin, a poor nuc leophile, was converted to a primary aliphatic amine by coupling with glyci ne. This glycylaminophenyl-porphyrin reacted readily with acyl azides deriv ed from extended Glu side-chains. These systems offer access to novel polym eric porphinatomanganese(III) agents for contrast enhancement in MRI.