Not less than 95.0%
(2S,3aS,7aS)-1-[(2S)-2-[[(1S)-1-(Ethoxycarbonyl)butyl]amino]-1-oxopropyl]octahydro-1H-indole-2-carboxylic Acid; [2S-[1[R*(R*)],2α,3aβ,7aβ]]-1-[2-[[1-(Ethoxycarbonyl) butyl]amino]-1-oxopropyl]octahydro-1H-indole-2-carboxylic Acid