tert-Butyl mercaptan → HCID 89668271, compound

Participants

Reaction Steps

A 0.4 M aqueous tris(2-carboxyethyl)phosphine (TCEP) solution (0.428 ml, 0.171 mmol) was added to a solution of (S)-benzyl 2-((tert-butoxycarbonyl)amino)-5-(((R)-1-ethoxy-3-mercapto-1-oxopropan-2-yl)amino)-5-oxopentanoate (Compound 3a) (20.0 mg, 0.0427 mmol) in DMF (0.8 ml), and the mixture was stirred at room temperature for 15 minutes. tBuSH (0.0144 ml, 0.128 mmol) and a 1 M aqueous 2,2′-azobis-2-(2-imidazolin-2-yl)propane (VA-044) solution (0.0427 ml, 0.0427 mmol) were then added and the mixture was stirred at 50° C. for 2.5 hours. The reaction solution was then diluted by adding water, and subsequent purification by reverse-phase silica gel column chromatography (10 mM aqueous ammonium acetate solution/methanol=70/30→20/80) afforded (S)-benzyl 2-((tert-butoxycarbonyl)amino)-5-(((S)-1-ethoxy-1-oxopropan-2-yl)amino)-5-oxopentanoate (Compound 3b) (18.1 mg, 97%).

Provenance & Evidence