l-Isoleucine

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  • Identifiers

    CAS number
    73-32-5

    Molecular formula
    C6H13NO2

    SMILES
    CC[C@H](C)[C@@H](C(=O)O)N

  • Odor profile

    Fragrance
    Odorless 66.32%
    Cooling 37.8%
    Mint 31.64%
    Savory 24.33%
    Milky 18.9%
    Bitter 18.1%
    Cheesy 17.36%
    Grapefruit 16.43%
    Malty 14.82%
    Fresh 14.57%

     

    Flavor
    Odorless 45.97%
    Mild 28.94%
    Bland 25.05%
    Sulfury 20.07%
    Acrid 20.0%
    Yeasty 19.86%
    Stinky 19.8%
    Bloody 19.55%
    Roquefort cheese 19.25%
    Cedarleaf 19.13%

     

    Odor impact est.
    Low

  • Properties

    XLogP3-AA
    -1.7

    pKa est.
    6.48 (neutral)

    Molecular weight
    131.17 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Very slow

    Melting point expt.

    • 285.5 dec °C
    • 284 °C (decomposes)
    • 285.5 °C

    Boiling point

    • Sublimes at 168-170 °C

    Flash point

    • 110.32 ˚C est.

    Solubility expt.

    • 34400 mg/L (at 25 °C)
    • Glistening rhombic or monoclinic plates from dilute alcohol. Decomposes at 292 °C. pK1 = 2.32; pK2 = 9.76. Solubility in water (g/L): 18.3 at 0 °C; 22.3 at 25 °C; 30.3 at 50 °C; 46.1 at 75 °C; 78.0 at 100 °C /Isoleucine, DL-form/
    • Sparingly soluble in hot alcohol (0.13% wt/wt at 80 °C), hot acetic acid. Insoluble in ether.
    • Solubility in water (g/L): 37.9 at 0 °C; 41.2 at 25 °C; 48.2 at 50 °C; 60.8 at 75 °C; 82.6 at 100 °C
    • In water, 3.44X10+4 mg/L at 25 °C
    • 35 mg/mL
    • Soluble in 0.26 mM phosphate buffer pH 7.1; soluble in propylene glycol
    • Soluble (in ethanol)

  • Synonyms

    • l-isoleucine
    • Isoleucine
    • 73-32-5
    • (2S,3S)-2-Amino-3-methylpentanoic acid
    • H-Ile-OH
    • 2S,3S-Isoleucine
    • (S)-Isoleucine
    • (S,S)-Isoleucine
    • 2-Amino-3-methylvaleric acid
    • L-(+)-Isoleucine
    • erythro-L-Isoleucine
    • L-Ile
    • ISOLEUCINE, L-
    • alpha-Amino-beta-methylvaleric acid
    • Isoleucine (VAN)
    • Isoleucinum [Latin]
    • Isoleucina
    • Isoleucina [Spanish]
    • Norvaline, 3-methyl-
    • Valeric acid, 2-amino-3-methyl-
    • L-Norvaline, 3-methyl-, erythro-
    • Pentanoic acid, 2-amino-3-methyl-
    • Acetic acid, amino-sec-butyl-
    • CCRIS 5229
    • iso-leucine
    • ile
    • (2S,3S)-alpha-Amino-beta-methyl-n-valeric acid
    • MFCD00064222
    • NSC 46708
    • (2S,3S)-alpha-Amino-beta-merthylvaleric acid
    • (S-(R*,R*))-2-Amino-3-methylpentanoic acid
    • FEMA No. 3295
    • (2S,3S)-alpha-Amino-beta-merthyl-n-valeric acid
    • 2-Amino-3-methylpentanoic acid, (S-(R*,R*))-
    • Acetic acid, amino(1-methylpropyl)-, (R*,R*)-
    • Isoleucine (L-Isoleucine)
    • 5HX0BYT4E3
    • Pentanoic acid, 2-amino-3-methyl-, (S-(R*,R))-
    • DTXSID2046882
    • FEMA NO. 4675
    • CHEBI:17191
    • [S-(R*,R*)]-2-Amino-3-methylpentanoic acid
    • 2S-Amino-3S-methylpentanoic acid
    • Isoleucine, DL-
    • DL-Allo-isoleucine
    • MFCD00004268
    • NSC-46708
    • 04Y7590D77
    • (2S,3S)-alpha-Amino-beta-methylvaleric acid
    • Pentanoic acid, 2-amino-3-methyl-, (2S,3S)-
    • Isoleucinum
    • DTXCID201323037
    • Isoleucine [USAN:INN]
    • CAS-443-79-8
    • (2S,3S)-2-amino-3-methylpentanoate
    • EINECS 200-798-2
    • UNII-5HX0BYT4E3
    • (2S,3S)-2-Amino-3-methylpentanoicacid
    • NSC-9958
    • NSC46708
    • L-iso-leucine
    • HSDB 7798
    • (L)-Isoleucine
    • L- iso-Leucine
    • Isoleucine [USAN:USP:INN:BAN]
    • UNII-04Y7590D77
    • NCGC00181164-01
    • Isoleucine (USP)
    • NSC 9958
    • EINECS 207-139-8
    • H-Ile
    • Ile-OH
    • (+)-L-isoleucine
    • L-[14C]Isoleucine
    • (2S,3S)-a-Amino-b-methylvaleric acid
    • ISOLEUCINE [II]
    • ISOLEUCINE [MI]
    • (2S,3S)-a-Amino-b-methyl-n-valeric acid
    • AI3-18474
    • L-Isoleucine (JP18)
    • ISOLEUCINE [INN]
    • (2S,3S)-2-amino-3-methyl-Pentanoic acid
    • ISOLEUCINE [HSDB]
    • ISOLEUCINE [USAN]
    • ISOLEUCINE DL-FORM
    • 2-Amino-3-methylvalerate
    • ISOLEUCINE [VANDF]
    • Isoleucine, L- (8CI)
    • bmse000041
    • bmse000866
    • bmse000884
    • 2-amino-3-methylpentanoate
    • ISOLEUCINE [MART.]
    • L-Isoleucine (H-lle-OH)
    • L-ISOLEUCINE [FCC]
    • L-ISOLEUCINE [JAN]
    • SCHEMBL8869
    • DL-ISOLEUCINE [FCC]
    • ISOLEUCINE [WHO-DD]
    • sec-C4H9CH(NH2)COOH
    • DL-ISOLEUCINE [FHFI]
    • L-Isoleucine (H-L-Ile-OH)
    • L-ISOLEUCINE [USP-RS]
    • GTPL3311
    • CHEMBL1233584
    • DTXSID1047441
    • ISOLEUCINE DL-FORM [MI]
    • BDBM18140
    • Norvaline, 3-methyl-, erythro-
    • ISOLEUCINE [EP MONOGRAPH]
    • ISOLEUCINE [USP MONOGRAPH]
    • L-Isoleucine, 99%, FCC, FG
    • Pharmakon1600-01301004
    • (2S,3S)-a-Amino-b-methylvalerate
    • HY-N0771
    • Tox21_112765
    • LMFA01100047
    • NSC760109
    • s3752
    • L-Isoleucine, Vetec(TM), 98.5%
    • AKOS015842027
    • Tox21_112765_1
    • (2S,3S)-a-Amino-b-methyl-n-valerate
    • CCG-266114
    • CS-W018502
    • DB00167
    • FD20022
    • FI12675

  • Applications

    L-Isoleucine (CAS 73-32-5) is an essential amino acid widely employed in food, feed, pharmaceutical and sports-nutrition industries for its ability to stimulate skeletal-muscle protein synthesis, support muscle recovery, modulate blood glucose, enhance hemoglobin formation and endurance, serving as a key component of parenteral amino-acid infusions for malnourished or postoperative patients, a micronutrient in infant formula, energy drinks and nutrition bars, a building block in peptide synthesis, a natural flavor enhancer and a cell-culture medium ingredient, as well as a growth-promoting feed additive that improves feed conversion, immunity and meat quality in livestock.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 1.02
    methanol 3.23
    isopropanol 2.04
    water 19.74
    ethyl acetate 0.74
    n-propanol 0.58
    acetone 0.1
    n-butanol 0.37
    acetonitrile 0.58
    DMF 0.6
    toluene 0.27
    isobutanol 1.59
    1,4-dioxane 2.12
    methyl acetate 2.51
    THF 2.93
    2-butanone 0.8
    n-pentanol 0.75
    sec-butanol 1.42
    n-hexane 0.11
    ethylene glycol 14.7
    NMP 21.92
    cyclohexane 0.11
    DMSO 11.23
    n-butyl acetate 2.12
    n-octanol 1.48
    chloroform 0.97
    n-propyl acetate 0.65
    acetic acid 16.06
    dichloromethane 0.77
    cyclohexanone 3.0
    propylene glycol 9.71
    isopropyl acetate 0.77
    DMAc 5.31
    2-ethoxyethanol 4.31
    isopentanol 1.11
    n-heptane 0.19
    ethyl formate 1.08
    1,2-dichloroethane 0.53
    n-hexanol 3.36
    2-methoxyethanol 4.75
    isobutyl acetate 0.71
    tetrachloromethane 1.12
    n-pentyl acetate 1.75
    transcutol 12.91
    n-heptanol 3.09
    ethylbenzene 0.43
    MIBK 0.97
    2-propoxyethanol 10.24
    tert-butanol 4.28
    MTBE 1.15
    2-butoxyethanol 7.64
    propionic acid 8.32
    o-xylene 1.04
    formic acid 52.74
    diethyl ether 0.18
    m-xylene 0.81
    p-xylene 0.74
    chlorobenzene 0.7
    dimethyl carbonate 0.73
    n-octane 0.12
    formamide 14.82
    cyclopentanone 3.33
    2-pentanone 0.34
    anisole 0.84
    cyclopentyl methyl ether 1.45
    gamma-butyrolactone 10.02
    1-methoxy-2-propanol 3.75
    pyridine 1.08
    3-pentanone 0.53
    furfural 14.44
    n-dodecane 0.1
    diethylene glycol 24.69
    diisopropyl ether 0.37
    tert-amyl alcohol 5.49
    acetylacetone 1.51
    n-hexadecane 0.11
    acetophenone 2.28
    methyl propionate 0.97
    isopentyl acetate 3.55
    trichloroethylene 1.76
    n-nonanol 1.48
    cyclohexanol 2.0
    benzyl alcohol 2.22
    2-ethylhexanol 3.14
    isooctanol 3.45
    dipropyl ether 0.47
    1,2-dichlorobenzene 1.7
    ethyl lactate 2.61
    propylene carbonate 6.01
    n-methylformamide 1.39
    2-pentanol 0.66
    n-pentane 0.05
    1-propoxy-2-propanol 6.84
    1-methoxy-2-propyl acetate 4.76
    2-(2-methoxypropoxy) propanol 10.65
    mesitylene 0.98
    ε-caprolactone 5.62
    p-cymene 1.55
    epichlorohydrin 3.73
    1,1,1-trichloroethane 0.96
    2-aminoethanol 8.88
    morpholine-4-carbaldehyde 10.32
    sulfolane 41.68
    2,2,4-trimethylpentane 0.27
    2-methyltetrahydrofuran 2.7
    n-hexyl acetate 2.31
    isooctane 0.21
    2-(2-butoxyethoxy)ethanol 10.45
    sec-butyl acetate 0.79
    tert-butyl acetate 2.1
    decalin 0.31
    glycerin 29.77
    diglyme 12.37
    acrylic acid 11.87
    isopropyl myristate 1.1
    n-butyric acid 3.15
    acetyl acetate 1.28
    di(2-ethylhexyl) phthalate 4.42
    ethyl propionate 0.68
    nitromethane 6.1
    1,2-diethoxyethane 1.13
    benzonitrile 1.55
    trioctyl phosphate 3.14
    1-bromopropane 0.17
    gamma-valerolactone 8.77
    n-decanol 1.2
    triethyl phosphate 2.43
    4-methyl-2-pentanol 1.33
    propionitrile 0.37
    vinylene carbonate 4.54
    1,1,2-trichlorotrifluoroethane 19.45
    DMS 3.16
    cumene 0.88
    2-octanol 1.75
    2-hexanone 0.52
    octyl acetate 1.69
    limonene 1.78
    1,2-dimethoxyethane 2.08
    ethyl orthosilicate 2.22
    tributyl phosphate 2.66
    diacetone alcohol 7.41
    N,N-dimethylaniline 1.38
    acrylonitrile 0.82
    aniline 0.97
    1,3-propanediol 5.24
    bromobenzene 0.59
    dibromomethane 0.49
    1,1,2,2-tetrachloroethane 2.36
    2-methyl-cyclohexyl acetate 4.2
    tetrabutyl urea 3.16
    diisobutyl methanol 2.3
    2-phenylethanol 5.14
    styrene 0.28
    dioctyl adipate 2.07
    dimethyl sulfate 4.14
    ethyl butyrate 1.34
    methyl lactate 4.07
    butyl lactate 4.19
    diethyl carbonate 1.12
    propanediol butyl ether 8.3
    triethyl orthoformate 1.72
    p-tert-butyltoluene 1.57
    methyl 4-tert-butylbenzoate 8.8
    morpholine 1.82
    tert-butylamine 1.53
    n-dodecanol 0.94
    dimethoxymethane 0.61
    ethylene carbonate 2.89
    cyrene 16.85
    2-ethoxyethyl acetate 3.16
    2-ethylhexyl acetate 2.49
    1,2,4-trichlorobenzene 2.66
    4-methylpyridine 0.81
    dibutyl ether 0.36
    2,6-dimethyl-4-heptanol 2.3
    DEF 0.8
    dimethyl isosorbide 20.76
    tetrachloroethylene 3.16
    eugenol 9.2
    triacetin 4.34
    span 80 10.86
    1,4-butanediol 4.08
    1,1-dichloroethane 0.35
    2-methyl-1-pentanol 1.9
    methyl formate 1.85
    2-methyl-1-butanol 1.33
    n-decane 0.13
    butyronitrile 0.28
    3,7-dimethyl-1-octanol 2.05
    1-chlorooctane 0.44
    1-chlorotetradecane 0.26
    n-nonane 0.11
    undecane 0.11
    tert-butylcyclohexane 0.36
    cyclooctane 0.12
    cyclopentanol 3.93
    tetrahydropyran 0.58
    tert-amyl methyl ether 1.4
    2,5,8-trioxanonane 14.23
    1-hexene 0.18
    2-isopropoxyethanol 4.05
    2,2,2-trifluoroethanol 15.48
    methyl butyrate 0.9

    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