Molecule structure of ((S)-2-Azetidinecarboxylic acid (CAS NO.2133-34-8):

IUPAC Name: (2S)-Azetidine-2-carboxylic acid 
Molecular Weight: 101.10388 g/mol
Molecular Formula: C₄H₇NO₂ 
Density: 1.275 g/cm³ 
Melting Point: ~215 °C (dec.)
Boiling Point: 242 °C at 760 mmHg 
Flash Point: 100.1 °C
Index of Refraction: 1.499
Molar Refractivity: 23.29 cm³
Molar Volume: 79.2 cm³
Polarizability: 9.23×10^-24 cm³
Surface Tension: 48.2 dyne/cm 
Enthalpy of Vaporization: 52.75 kJ/mol
Vapour Pressure: 0.0116 mmHg at 25 °C 
Storage Temp.: 2-8 °C
Water Solubility: 5 g/100 mL
XLogP3: -2.9
H-Bond Donor: 2
H-Bond Acceptor: 3
Rotatable Bond Count: 1
Exact Mass: 101.047678
MonoIsotopic Mass: 101.047678
Topological Polar Surface Area: 49.3
Heavy Atom Count: 7
Complexity: 91.7
Canonical SMILES: C1CNC1C(=O)O
Isomeric SMILES: C1CN[C@@H]1C(=O)O
InChI: InChI=1S/C4H7NO2/c6-4(7)3-1-2-5-3/h3,5H,1-2H2,(H,6,7)/t3-/m0/s1
InChIKey: IADUEWIQBXOCDZ-VKHMYHEASA-N
EINECS: 218-362-5
Product Categories: Pharmaceutical Raw Materials; Nitrogen cyclic compounds; Miscellaneous;pharmacetical; chiral; API; Amino Acids 13C, 2H, 15N; Carboxylic Acids (Chiral); Azetidines; Chiral Building Blocks; Simple 4-Membered Ring Compounds; Synthetic Organic Chemistry; Amino Acids & Derivatives

 ((S)-2-Azetidinecarboxylic acid has been known since 1955 to be present in rhizomes and fresh foliage of certain plants. It is known to occur in one species, Convallaria majalis (lily of the valley), from the lily family, Liliaceae, and one species, Polygonatum officinale, from the flowering plant family, Ruscaceae. Lily of the ValleyAze is also found in numerous plants from the family Fabaceae, and has also been detected in small quantities in table beets, garden beets, and sugar beets.

 ((S)-2-Azetidinecarboxylic acid (CAS NO.2133-34-8) is a four-membered ring analog of L-Proline. It is a useful intermediate in the synthesis of polypeptides.

An optically active ((S)-2-Azetidinecarboxylic acid was obtained by treatment of αγ-diaminobutyric acid dihydrochloride with a mixture of nitrous and hydrochloric acids to yield γ-amino-α-chlorobutyric acid, followed by elimintation of hydrogen chloride and cyclization by treatment with barium hydroxide. Optically inactive ((S)-2-Azetidinecarboxylic acid was obtained in small yield from γ-aminobutyric acid by α-bromination, followed by removal of hydrogen bromide from the intermediate γ-amino-α-butyric acid and ring closure by treatment with a barium hydroxide solution.

Hazard Codes: Xi
Risk Statements: 36/37/38 
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements: 24/25-36-26 
S24/25:Avoid contact with skin and eyes. 
S36:Wear suitable protective clothing. 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
WGK Germany: 3
RTECS: CM4310500
Hazard Note: Irritant
Hazardous Substances Data: 2133-34-8(Hazardous Substances Data)
Moderately toxic by subcutaneous route. An experimental teratogen. Other experimental reproductive effects. When heated to decomposition it emits toxic fumes of NO_x.

 ((S)-2-Azetidinecarboxylic acid (CAS NO.2133-34-8) is also named as 2-Azetidinecarboxylic acid, (S)- ; 2-Azetidinecarboxylic acid, L- ; Acide L-azetidine-2-carboxylic ; Acide L-azetidine-2-carboxylic [French] ; Azetidinecarboxylic acid ; HSDB 3465 ; L-Azetidine-2-carboxylic acid ; (S)-Azetidine-2-carboxylic acid ; 2-Azetidinecarboxylic acid, (S)- (9CI) . ((S)-2-Azetidinecarboxylic acid (CAS NO.2133-34-8) is white to light yellow crystal powder. It is toxic. It is flammable. It will produce toxic nitrogen oxide fumes when buring. So the storage environment should be ventilate, low-temperature and dry.