Methyl 2-oxo-3-phenylpropanoate → 3-(S)-amino-1-[1-carboxy-2-phenylethyl]perhydroazepin-2-one

Participants

Reaction Steps

Methyl 2-oxo-3-phenylpropionate and α-t-Boc-L-lysine are condensed in the presence of sodium cyanoborohydride as described in Example 19. Subsequent ring closure to 3-(S)-t-butoxycarbonylamino-1-[1-carbomethoxy-2-phenylethyl]perhydroazepin-2-one is carried out as described in Example 3. Saponification of the methyl ester followed by removal of the t-butoxycarbonyl group affords 3-(S)-amino-1-[1-carboxy-2-phenylethyl]perhydroazepin-2-one. The caprolactam and 2-oxo-4-phenylbutyric acid are condensed in the presence of sodium cyanoborohydride to yield 1-[1-carboxy-2-phenylethyl]-3-(S)-[(1-carboxy-3-phenylpropyl)amino]perhydroazepin-2-one.

Provenance & Evidence