Trifluoroacetic acid → (2S,4S)-4-Mercapto-2-[4-(N-4-nitrobenzyloxycarbonylacetimidoyl)homopiperazin-1-ylcarbonyl]-1-(4-nitrobenzyloxycarbonyl)pyrrolidine Trifluoromethanesulfonate

Participants

Reaction Steps

2.1 ml of trifluoroacetic acid and 67 μl of trifluoromethanesulfonic acid were added to a solution of 285 mg of (2S,4S)-4-(4-methoxybenzylthio)-2-[4-(N-4-nitrobenzyloxycarbonylacetimidoyl)homopiperazin-1-ylcarbonyl]-1-(4-nitrobenzyloxycarbonyl)pyrrolidine [prepared as described in step (ii) above] in 414 μl of anisole, and the resulting mixture was stirred for 1 hour, whilst ice-cooling. At the end of this time, the reaction mixture was worked up by the same procedure as described in Preparation 1(iv), to give 296 mg of the title compound, as a powder.

Provenance & Evidence