Following the procedure described for the preparation of (3S)-3-({N-[(4-methoxy-1H-indol-2-yl)carbonyl]-l-leucyl}amino)-2-oxo-4-[(3S)-2-oxopyrrolidin-3-yl]butyl acetate but substituting 2,6-dimethylbenzoic acid and making noncritical variations provided a crude brown foam.