4-[({(2S,4S)-1-(4-carbamimidoylbenzoyl)-4-[4-(methylsulfonyl)-1-piperazinyl]-2-pyrrolidinyl}carbonyl)amino]benzoic acid bis(trifluoroacetate) → ethyl 4-[({(2S,4S)-1-(4-carbamimidoylbenzoyl)-4-[4-(methylsulfonyl)-1-piperazinyl]-2-pyrrolidinyl}carbonyl)amino]benzoate bis(trifluoroacetate)

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of compound prepared in Example 20 (500 mg) in ethanol (25 mL) was added concentrated sulfuric acid (20 drops) at 0° C. The resulting mixture was stirred at 60° C. for 44 h whereupon the mixture was concentrated in vacuo. The resulting residue was purified by Prep-HPLC (0.1% TFA containing CH3CN—H2O gradient) to provide the title compound (307 mg).

Provenance & Evidence