Sodium Hydroxide → 1-[2-Acetylthiomethyl-5-(trifluoroacetylamino)pentanoyl]-L-proline

Participants

Reaction Steps

A mixture of 2-acetylthiomethyl-5-aminopentanoic acid (2.05 g.) and p-nitrophenyltrifluoroacetate (5.6 g.) in pyridine (10 ml.) is stirred at room temperature for four hours, and then added dropwise to a vigorously stirred solution of L-proline (1.55 g.) in water (10 ml.) while keeping the pH at 9 with careful addition of 2N sodium hydroxide. When the consumption of sodium hydroxide stops, the reaction mixture is acidified with hydrochloric acid and extracted with ethyl acetate. The solvent is removed in vacuo and the residue is chromatographed on a silica gel column to yield 1-[2-acetylthiomethyl-5-(trifluoroacetylamino)pentanoyl]-L-proline.

Provenance & Evidence