Hydrochloric Acid → HCID 70386019, compound

Participants

Reaction Steps

A 300 mg portion of maleate of β-isomer of N-[(R)-1-ethoxycarbonyl-2-cyclopentylthioethyl]-alanyl-(S)-proline methyl ester prepared in Example 57 was dissolved in 2 ml of ethanol. To the solution was added dropwise 2.9 ml of 1N-NaOH at room temperature. The mixture was stirred overnight and neutralized with 2N-HCl with ice cooling. The solvent was completely removed by distillation. The residue was dissolved in methanol and the solution was subjected to high performance liquid chromatography (column=Chemcosorb 7-ODS-H, eluent=a 50:50:0.4 mixture of methanol, water and acetic acid) for separation. The solvent was distilled off. After addition of 4 ml of ether, the precipitated crystals were collected by filtration, giving the title compound as white crystals. Yield 160 mg.

Provenance & Evidence