The solid-phase method of peptide synthesis, with an ABIMED AMS 422 synthesizer and a Rink amide resin have been used. N-Fmoc-L-Leucine (I) was attached to Rink amide resin using benzotriazol-1-yloxytripyrrolidinophosphonium hexafluorophosphate as the coupling reagent, and the Fmoc protecting group was subsequently removed to afford resin (II). Further coupling and deprotection cycles with N-Fmoc-L-tyrosine(O-t--Bu) (III), N-Fmoc-N-Boc-L-lysine (V) and again N-Fmoc-N-Boc-L-lysine (V) provided peptide resins (IV), (VI) and (VII), respectively.

Peptide resin (VII) was then coupled with stearic acid to yield (VIII). Finally, the target peptide amide was deprotected and cleaved from the resin by means of a mixture of trifluoroacetic acid, water and triethylsilane.

The solid-phase method of peptide synthesis, with an ABIMED AMS 422 synthesizer and a Rink amide resin have been used. N-Fmoc-L-Leucine (I) was attached to Rink amide resin using benzotriazol-1-yloxytripyrrolidinophosphonium hexafluorophosphate as the coupling reagent, and the Fmoc protecting group was subsequently removed to afford resin (II). Further coupling and deprotection cycles with N-Fmoc-L-tyrosine(O-t--Bu) (III), N-Fmoc-N-Boc-L-lysine (V) and again N-Fmoc-N-Boc-L-lysine (V) provided peptide resins (IV), (VI) and (VII), respectively.

Peptide resin (VII) was then coupled with stearic acid to yield (VIII). Finally, the target peptide amide was deprotected and cleaved from the resin by means of a mixture of trifluoroacetic acid, water and triethylsilane.