Influence of the dipeptide linker configuration on the activity of PSMA ligands

Selective ligands of an urea-based prostate specific membrane antigen with a phenylalanine/tyrosine-based dipeptide linker and with a mingled chiral centers configuration and/or substituted aromatic fragments were prepared in seven steps by liquid- and in six steps by solid-phase synthesis. In vitro test for inhibiting the cleavage of N-acetylaspartylglutamate revealed the optimum linker containing l-phenylalanine in the structure on the N-terminus of a dipeptide chain.