HCID 86745736, compound → HCID 18639814, compound

Participants

Reaction Steps

A solution of 2-[3-acetylmercapto-6-methyl-4-[[[1-(S)-[(methylamino)carbonyl]-2-(4-methoxyphenyl)ethyl]amino]carbonyl]heptanoylamino]ethanoic acid, t-butyl ester (E12, Isomer A; 60 mg, 0.11 mmol) in trifluoroacetic acid (1.5 ml) and water (0.05 ml) was stirred in an ice bath for 1 h, then at room temperature for 2 h. The solvent was evaporated in vacuo and the residue was azeotroped dry with toluene to leave the title compound as a single isomer (Isomer A), mp 188°-192° C.

Provenance & Evidence