Trifluoroacetic acid → (2S,4S)-2-[4-(2-Carbamoyloxyethyl)-1-piperazinylcarbonyl]-4-mercapto-1-(4-nitrobenzyloxycarbonyl)pyrrolidine trifluoromethanesulfonate

Participants

Reaction Steps

2.67 ml of trifluoroacetic acid and 122 μl of trifluoromethanesulfonic acid were added, whilst ice-cooling, to a solution of 417 mg of (2S,4S)-4-(4-methoxybenzylthio)-2-[4-(2-carbamoyloxyethyl)-1-piperazinylcarbonyl]-1-(4-nitrobenzyloxycarbonyl)pyrrolidine [prepared as described in step (ii) above] in 753 μl of anisole, and the resulting mixture was stirred at the same temperature for 1 hour. At the end of this time, the solvent was removed by distillation under reduced pressure, and the residue was repeatedly washed with diethyl ether by decantation. After the residue had been dried in vacuo, 325 mg of the title compound were obtained, as a powder.

Provenance & Evidence