(2R,3S)-3-Amino-2-methyl-4-oxo-1-azetidinesulfonic Acid 
Synonyms: (2R,3S)-3-Amino-2-methyl-4-oxo-1-azetidinesulfonic Acid  
 (2S-Trans)-3-Amino-2-Methyl-4-Oxo-1-Azetidinesulfonic Acid 
(3s-trans)-3-amino-4-methyl-2-oxo-1-azetidinesulfonic acid 
Structure:
CAS #: 80082-65-1
Molecular formula: C₄H₈N₂O₄S
Molecular weight: 180.18
Assay: 98% (HPLC)
Uses: pharmaceutical intermediate, eg: Azteronam.