2-Azetidinecarboxylic acid, (S)-

Overview IFRA Request a quote

  • Identifiers

    CAS number
    2133-34-8

    Molecular formula
    C4H7NO2

    SMILES
    C1CN[C@@H]1C(=O)O

    Safety labels

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Odorless 77.82%
    Sweet 29.4%
    Nutty 22.46%
    Savory 18.98%
    Caramellic 18.61%
    Popcorn 18.25%
    Ethereal 16.53%
    Bitter 16.48%
    Burnt 15.72%
    Buttery 15.71%

     

    Flavor
    Odorless 53.84%
    Bitter 48.12%
    Very mild 25.5%
    Mild 23.13%
    Bland 22.8%
    Sweet-like 21.89%
    Yeast 21.46%
    Taco 19.67%
    Formyl 19.56%
    Urine 19.53%

     

    Odor impact est.
    Low

  • Properties

    XLogP3-AA
    -2.9

    pKa est.
    7.62 (neutral)

    Molecular weight
    101.1 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Slow

    Boiling point est.
    232°C

    Flash point

    • 131.93 ˚C est.

    Solubility expt.

    • SOL IN COLD & HOT WATER; PRACTICALLY INSOL IN ABSOLUTE ETHANOL

  • Synonyms

    • (S)-Azetidine-2-carboxylic acid
    • (2S)-azetidine-2-carboxylic acid
    • (S)-2-Azetidinecarboxylic acid
    • 2-Azetidinecarboxylic acid, (S)-
    • 2-Azetidinecarboxylic acid, (2S)-
    • (S)-(-)-2-azetidine carboxylic acid
    • CHEBI:6198
    • RefChem:25831
    • 218-362-5
    • 2133-34-8
    • L-Azetidine-2-carboxylic acid
    • (S)-(-)-2-Azetidinecarboxylic acid
    • Azetidyl-2-carboxylic acid
    • (S)-(-)-Azetidine-2-carboxylic acid
    • MFCD00005166
    • L-Azetidine 2-carboxylic acid
    • (L)-AZETIDINE-2-CARBOXYLIC ACID
    • Azetidine-2-carboxylic acid, L-
    • 2-Azetidinecarboxylic acid, L-
    • (S)-L-Azetidine-2-carboxylic acid
    • C4H7NO2
    • 5GZ3E0L9ZU
    • L-2-Azetidinecarboxylic acid
    • Acide L-azetidine-2-carboxylic
    • CHEMBL1165239
    • L-azetidine-2-carboxylate
    • (2S)azetidine-2-carboxylic acid
    • ST059592
    • (2s)-2-azetidinecarboxylic acid
    • azetidine-2-carboxylate
    • (S)-Azetidine-2-carboxylicacid
    • HSDB 3465
    • AzeOH
    • 02A
    • (S)-2-Azetidinecarboxylic acid;H-Aze-OH
    • EINECS 218-362-5
    • L-AzeOH
    • L-Trimethyleneimine-2-carboxylic Acid
    • (S)-(-) Azetidine-2-carboxylic acid
    • Acide L-azetidine-2-carboxylic [French]
    • H-Aze(2)-OH
    • UNII-5GZ3E0L9ZU
    • L-azetidine-2caboxylic acid
    • (S)-Azetidin-2-carbonsaure
    • L-azetidine-2carboxylic acid
    • Lopac0_000023
    • SCHEMBL20296
    • (S)-2-azetidinecarboxyic acid
    • GTPL4686
    • orb1296944
    • SCHEMBL2223619
    • 2-(S)-azetidinecarboxylic acid
    • azetidine-2(S)-carboxylic acid
    • L--Azetidine-2-carboxylic acid
    • DTXSID0044020
    • (S)-2-azetidine carboxylic acid
    • azetidine-2-(S)-carboxylic acid
    • HMS3260E07
    • Tox21_500023
    • (-)-AZETIDINECARBOXYLIC ACID
    • BDBM50357225
    • SBB004365
    • AKOS005254687
    • AKOS006239010
    • (S)-(-)-2-azetidine-carboxylic acid
    • AC-5699
    • CCG-204119
    • EBC-253170
    • FA14215
    • HY-W050044
    • LP00023
    • SDCCGSBI-0050012.P002
    • L-Azetidine-2-carboxylic acid, >=99%
    • NCGC00093546-01
    • NCGC00093546-02
    • NCGC00093546-03
    • NCGC00093546-04
    • NCGC00260708-01
    • DS-16309
    • SY004809
    • AZETIDYL-2-CARBOXYLIC ACID [HSDB]
    • A1043
    • CS-0031389
    • EU-0100023
    • NS00048671
    • EN300-85821
    • A 0760
    • C08267
    • 133A348
    • AN-584/43509810
    • F040006
    • Q793715
    • SR-01000075656
    • SR-01000075656-1
    • L-Azetidine-2-carboxylic acid is known as a proline analog.
    • 2133-34-8

  • Applications

    2-Azetidinecarboxylic acid, (S)- is a chiral azetidine-based amino acid used mainly as a building block in medicinal chemistry. It serves as a conformationally restricted, small-ring amino acid scaffold for the design of peptidomimetics and constrained peptides, enabling exploration of structure-activity relationships. It is commonly used as an intermediate to access azetidine-containing heterocycles and other small-ring amino acid derivatives in drug-discovery programs. In synthetic chemistry, it can be employed as a chiral building block or auxiliary for asymmetric synthesis and for further functionalization to diversify drug-like molecules. Applications are typically in research and development contexts, subject to local regulations and formulation limits.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 1.74
    methanol 14.47
    isopropanol 0.46
    water 278.66
    ethyl acetate 0.37
    n-propanol 0.61
    acetone 0.76
    n-butanol 0.68
    acetonitrile 0.2
    DMF 6.5
    toluene 0.1
    isobutanol 0.55
    1,4-dioxane 1.04
    methyl acetate 0.19
    THF 1.96
    2-butanone 0.25
    n-pentanol 0.79
    sec-butanol 0.36
    n-hexane 0.07
    ethylene glycol 24.95
    NMP 34.87
    cyclohexane 0.07
    DMSO 54.69
    n-butyl acetate 1.19
    n-octanol 1.18
    chloroform 0.29
    n-propyl acetate 0.45
    acetic acid 37.11
    dichloromethane 0.57
    cyclohexanone 2.37
    propylene glycol 6.49
    isopropyl acetate 0.53
    DMAc 6.74
    2-ethoxyethanol 6.22
    isopentanol 1.21
    n-heptane 0.18
    ethyl formate 1.14
    1,2-dichloroethane 0.46
    n-hexanol 1.59
    2-methoxyethanol 11.04
    isobutyl acetate 0.36
    tetrachloromethane 0.19
    n-pentyl acetate 1.27
    transcutol 34.47
    n-heptanol 1.88
    ethylbenzene 0.12
    MIBK 1.12
    2-propoxyethanol 7.19
    tert-butanol 1.43
    MTBE 0.23
    2-butoxyethanol 7.32
    propionic acid 3.95
    o-xylene 0.29
    formic acid 204.2
    diethyl ether 0.13
    m-xylene 0.32
    p-xylene 0.2
    chlorobenzene 0.27
    dimethyl carbonate 0.56
    n-octane 0.1
    formamide 79.26
    cyclopentanone 2.65
    2-pentanone 0.53
    anisole 0.38
    cyclopentyl methyl ether 0.83
    gamma-butyrolactone 5.71
    1-methoxy-2-propanol 5.16
    pyridine 0.74
    3-pentanone 0.31
    furfural 15.34
    n-dodecane 0.07
    diethylene glycol 23.14
    diisopropyl ether 0.22
    tert-amyl alcohol 1.3
    acetylacetone 2.43
    n-hexadecane 0.08
    acetophenone 1.22
    methyl propionate 0.39
    isopentyl acetate 1.5
    trichloroethylene 0.88
    n-nonanol 1.25
    cyclohexanol 1.11
    benzyl alcohol 1.42
    2-ethylhexanol 1.3
    isooctanol 1.91
    dipropyl ether 0.5
    1,2-dichlorobenzene 0.59
    ethyl lactate 2.1
    propylene carbonate 4.04
    n-methylformamide 5.45
    2-pentanol 0.44
    n-pentane 0.05
    1-propoxy-2-propanol 4.78
    1-methoxy-2-propyl acetate 2.7
    2-(2-methoxypropoxy) propanol 11.51
    mesitylene 0.44
    ε-caprolactone 3.28
    p-cymene 0.6
    epichlorohydrin 2.33
    1,1,1-trichloroethane 0.2
    2-aminoethanol 13.61
    morpholine-4-carbaldehyde 19.76
    sulfolane 30.47
    2,2,4-trimethylpentane 0.09
    2-methyltetrahydrofuran 0.93
    n-hexyl acetate 1.61
    isooctane 0.11
    2-(2-butoxyethoxy)ethanol 15.27
    sec-butyl acetate 0.38
    tert-butyl acetate 1.22
    decalin 0.1
    glycerin 35.85
    diglyme 18.0
    acrylic acid 9.98
    isopropyl myristate 0.89
    n-butyric acid 4.06
    acetyl acetate 0.92
    di(2-ethylhexyl) phthalate 3.34
    ethyl propionate 0.4
    nitromethane 10.92
    1,2-diethoxyethane 1.6
    benzonitrile 0.9
    trioctyl phosphate 2.28
    1-bromopropane 0.11
    gamma-valerolactone 11.13
    n-decanol 1.05
    triethyl phosphate 1.45
    4-methyl-2-pentanol 0.98
    propionitrile 0.14
    vinylene carbonate 3.55
    1,1,2-trichlorotrifluoroethane 14.69
    DMS 1.6
    cumene 0.26
    2-octanol 0.99
    2-hexanone 0.48
    octyl acetate 1.24
    limonene 0.71
    1,2-dimethoxyethane 3.69
    ethyl orthosilicate 1.29
    tributyl phosphate 2.46
    diacetone alcohol 5.54
    N,N-dimethylaniline 0.84
    acrylonitrile 0.43
    aniline 0.56
    1,3-propanediol 9.2
    bromobenzene 0.18
    dibromomethane 0.29
    1,1,2,2-tetrachloroethane 0.87
    2-methyl-cyclohexyl acetate 1.99
    tetrabutyl urea 3.99
    diisobutyl methanol 1.45
    2-phenylethanol 2.42
    styrene 0.11
    dioctyl adipate 1.94
    dimethyl sulfate 3.75
    ethyl butyrate 0.99
    methyl lactate 3.61
    butyl lactate 4.21
    diethyl carbonate 0.74
    propanediol butyl ether 11.43
    triethyl orthoformate 1.26
    p-tert-butyltoluene 0.63
    methyl 4-tert-butylbenzoate 5.53
    morpholine 1.35
    tert-butylamine 0.59
    n-dodecanol 0.84
    dimethoxymethane 1.88
    ethylene carbonate 2.1
    cyrene 14.93
    2-ethoxyethyl acetate 2.45
    2-ethylhexyl acetate 1.05
    1,2,4-trichlorobenzene 0.84
    4-methylpyridine 0.58
    dibutyl ether 0.51
    2,6-dimethyl-4-heptanol 1.45
    DEF 1.63
    dimethyl isosorbide 15.9
    tetrachloroethylene 1.19
    eugenol 8.29
    triacetin 3.94
    span 80 11.64
    1,4-butanediol 5.63
    1,1-dichloroethane 0.12
    2-methyl-1-pentanol 1.18
    methyl formate 4.04
    2-methyl-1-butanol 0.83
    n-decane 0.09
    butyronitrile 0.26
    3,7-dimethyl-1-octanol 1.61
    1-chlorooctane 0.28
    1-chlorotetradecane 0.18
    n-nonane 0.09
    undecane 0.08
    tert-butylcyclohexane 0.11
    cyclooctane 0.07
    cyclopentanol 1.67
    tetrahydropyran 0.31
    tert-amyl methyl ether 0.38
    2,5,8-trioxanonane 18.31
    1-hexene 0.11
    2-isopropoxyethanol 3.27
    2,2,2-trifluoroethanol 17.62
    methyl butyrate 0.7

    Scent© AI

1 4

IFRA standard 51

Recommendation
No restriction
Maximum acceptable concentrations in the finished product (%)
Category 1
Products applied to the lips
 No restriction Category 7A
Rinse-off products applied to the hair with some hand contact
 No restriction
Category 2
Products applied to the axillae
 No restriction Category 7B
Leave-on products applied to the hair with some hand contact
 No restriction
Category 3
Products applied to the face/body using fingertips
 No restriction Category 8
Products with significant anogenital exposure
 No restriction
Category 4
Products related to fine fragrance
 No restriction Category 9
Products with body and hand exposure, primarily rinse off
 No restriction
Category 5A
Body lotion products applied to the body using the hands (palms), primarily leave on
 No restriction Category 10A
Household care products with mostly hand contact
 No restriction
Category 5B
Face moisturizer products applied to the face using the hands (palms), primarily leave on
 No restriction Category 10B
Household care products with mostly hand contact, including aerosol/spray products (with potential leave-on skin contact)
 No restriction
Category 5C
Hand cream products applied to the hands using the hands (palms), primarily leave on
 No restriction Category 11A
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate without UV exposure
 No restriction
Category 5D
Baby Creams, baby Oils and baby talc
 No restriction Category 11B
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate with potential UV exposure
 No restriction
Category 6
Products with oral and lip exposure
 No restriction Category 12
Products not intended for direct skin contact, minimal or insignificant transfer to skin
 No restriction