Trifluoroacetic acid → 2-((S)-2-{(R)-2-amino-2-[4-((R)-2,3-dihydroxy-propoxy)-phenyl]-acetylamino}-3-phenyl-propionylamino)-thiazole-4-carboxylic acid methyl ester

Participants

Reaction Steps

To a solution of 2-((S)-2-{(R)-2-tert-butoxycarbonylamino-2-[4-((S)-2,2-dimethyl-[1,3]dioxolan4-ylmethoxy)-phenyl]-acetylamino}-3-phenyl-propionylamino)-thiazole-4-carboxylic acid methyl ester (170 mg, 0.25 mmol) in dichloromethane (2.0 mL) was added trifluoroacetic acid (0.5 mL, 6.5 mmol) at 0° C. The reaction was warmed to room temperature and stirred for 4 hours. The solvent was removed under vacuum and the residue was partitioned between ethyl acetate and saturated aqueous sodium bicarbonate solution. The aqueous layer was extracted with ethyl acetate and the extracts were combined, washed with brine and dried over sodium sulfate to give 2-((S)-2-{(R)-2-amino-2-[4-((R)-2,3-dihydroxy-propoxy)-phenyl]-acetylamino}-3-phenyl-propionylamino)-thiazole-4-carboxylic acid methyl ester as a foam (120 mg, 90%).

Provenance & Evidence