(2S)-4-acetyloxy-2-aminobutanoic acid (2S)-4-acetoxy-2-amino-butanoic acid (2S)-4-acetoxy-2-aminobutanoic acid (2S)-4-acetoxy-2-amino-butyric acid (2S)-4-acetyloxy-2-amino-butanoic acid (2S)-4-(acetyloxy)-2-aminobutanoic acid CHEBI:16288 C01077