(i) 4 M HCl/dioxane, (ii) Boc-Leu-OH, HATU, NMM, DMF, 0 °C, (iii) HATU, 4-MeO-2-indolecarboxylic acid, NMM, 0 °C, (iv) Pd/C, H2, EtOH (77%), (v) CsF, DMF, benzoylformic acid, 60 °C, and then MeOH, cat.