Fmoc-Dipeptide Building Blocks

The coupling of Fmoc dipeptides (Fmoc-Xaa-Gly-OH, Fmoc-Xaa-Pro-OH) is a convenient method for accelerating Fmoc-SPPS and decreasing the number of potential by-products. Employing the appropriate Fmoc dipeptide building blocks instead of coupling a penultimate Fmoc-Gly or Fmoc-Pro prevents diketopiperazine formation.