Hydrochloric Acid → HCID 131722026, compound

Participants

Reaction Steps

A solution of (R)-N5 -(Cbz)-N2 -(Diphenylacetyl)-(R)-N-[1-(4-methoxy-phenyl)ethyl]ornithine amide (5.7 g; 9.6 mmol; from step (d) above) and HCl (2 N; 6 mL) in MeOH (200 mL) was flushed with nitrogen prior to the addition of 10% Pd/C (w/w; 530 mg). The heterogeneous solution was briefly flushed with hydrogen and then stirred under 1 atmosphere of hydrogen for 3 hours. When the deprotection was complete, as determined by TLC analysis, the solution was filtered through a pad of Celite to remove the catalyst. The filtrate was then evaporated at reduced pressure to give the crude product. The residue from evaporation of the filtrate was dissolved in water (300 mL) and washed with diethyl ether (2×50 mL). The aqueous layer was adjusted to pH 12 with concentrated NH4OH, then extracted with EtOAc (3×200 mL). The combined organic extracts were washed with brine (200 mL), then dried (Na2SO4) and filtered. The filtrate was evaporated at reduced pressure to give 4.2 g (95%) of the sub-title compound (free base) as a white solid.

Provenance & Evidence