The peptides that carried a benzene equivalent of the backbone fragment (SA-B3, C3, and D3) were synthesized using a slightly altered strategy. With a benzene group, a dipeptide fragment was not required since the nucleophilicity of the aniline was sufficient for regular amide bond formation. Therefore, the fragments could be installed in Fmoc-protected form on solid phase, followed by regular coupling of Boc-Leucine. To prepare the Fmoc-protected building blocks we used commercially available amines except for the building block required Scheme 4: Synthesis of benzene backbone building blocks for peptides SA-B3, -C3, and -D3.