Synthesis of peptide containing inhibitors.
Reagents and conditions: (a) TFA, CH2Cl2; (b) 32, PyBOP, DIPEA, 84% over 2 steps; (c) 36, PyBOP, DIPEA, 92% over 2 steps; (d) LiOH, THF, H2O; (e) TFA, CH2Cl2; (f) HATU, HOBt, DIPEA, CH3CN, 33% over 3 steps; (g) HATU, HOBt, DIPEA, CH3CN, 32% over 3 steps; (h) TFA, iPr3SiH, CH2Cl2, 94%; (i) TFA, iPr3SiH, CH2Cl2, 89%; (j) N-octanoyl–imidazole, imidazole, DMAP, THF, 50 ° C, 66%; (k) octanoyl chloride, Et3N, 55%.