Water → HCID 67520332, compound

Participants

Reaction Steps

To a solution of methyl (2S)-5-{[(tert-butoxy) carbonyl]amino}-4-({[(tert-butoxy)carbonyl]amino}methyl)-2-[(triphenylmethyl)amino]pentanoate CV (180 mg; 0.29 mmol) in methanol (15 mL) was added 4 M aq NaOH (3 mL). The mixture was stirred at r.t. for 1 h. Water (20 mL) was then added and the methanol was removed under reduce pressure. The aqueous solution was acidified with 2 M HCl to pH˜5-6 and extracted with DCM. The combined organic layers were dried over anhydrous MgSO4 and evaporated to obtain the crude (2S)-5-{[(tert-butoxy)carbonyl]amino}-4-({[(tert-butoxy)carbonyl]amino}methyl)-2-[(triphenylmethyl)amino]pentanoic acid CVI (145 mg). This material was used directly for step 6. ESIMS found for C35H45N3O6 m/z 604.4 (M+H).

Provenance & Evidence