Alpha-methyldopa

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  • Identifiers

    CAS number
    55-40-3

    Molecular formula
    C10H13NO4

    SMILES
    CC(CC1=CC(=C(C=C1)O)O)(C(=O)O)N

    Safety labels

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Odorless 79.18%
    Savory 26.03%
    Bitter 20.63%
    Milky 20.33%
    Phenolic 20.33%
    Cooling 19.24%
    Burnt 16.82%
    Smoky 16.68%
    Sweet 16.53%
    Balsamic 16.19%

     

    Flavor
    Odorless 56.09%
    Bitter 53.75%
    Mild 38.15%
    Bland 33.36%
    Sweet-like 23.23%
    Very mild 20.44%
    Yeast 20.01%
    Orange flower 19.96%
    Nitrile 19.74%
    Cedarleaf 19.51%

     

    Odor impact est.
    Low

  • Properties

    XLogP3-AA
    -1.9

    pKa est.
    7.97 (neutral)

    Molecular weight
    211.21 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra slow

    Boiling point est.
    395°C

    Flash point

    • 213.03 ˚C est.

  • Synonyms

    • 55-40-3
    • DL-Methyldopa
    • 3-Hydroxy-alpha-methyl-DL-tyrosine
    • 555-29-3
    • 3-Hydroxy-alpha-methyltyrosine
    • Mulfasin
    • Metholes
    • 2-amino-3-(3,4-dihydroxyphenyl)-2-methylpropanoic acid
    • (+/-)-methyldopa
    • rac Alpha-Methyl DOPA
    • EINECS 209-088-7
    • .alpha.-Methyl dopa
    • Methyldopa (Racemic)
    • Methyldopa anhydrous, (+/-)-
    • L-(.alpha.-Md)
    • Dl-.alpha.-methyl dopa
    • .alpha.-Methyldopa, L-
    • EINECS 200-232-4
    • Racemic .alpha.-methyldopa
    • Aldomin
    • (+/-)-3-(3,4-dihydroxyphenyl)-2-methyl-DL-alanine
    • L-Methyldopa
    • 33TD13T99R
    • L-.alpha.-Methyldopa
    • .alpha.-Methyl-L-dopa
    • .alpha.-Methyl-L-(3,4-dihydroxyphenyl)alanine
    • L-.alpha.-Methyl-(3,4-dihydroxyphenyl)alanine
    • Aldomine
    • (S)-(-)-.alpha.-Methyldopa
    • .alpha.-Methyl-.beta.-(3,4-dihydroxyphenyl)-L-alanine
    • a-methyl-l-dopa
    • Nr.C 2294
    • DL-alpha-Methyl DOPA
    • L-(-)-.alpha.-Methyl-.beta.-(3,4-dihydroxyphenyl)alanine
    • NCI-C55721
    • racemic alpha-Methyldopa
    • (+-)-alpha-Methyldopa
    • MK 351
    • L-Tyrosine, 3-hydroxy-.alpha.-methyl-
    • 2-Methyl-3-(3,4-dihydroxyphenyl)alanine
    • Mk. b51
    • Tyrosine, 3-hydroxy-alpha-methyl-
    • SR-01000075631
    • Elanpres
    • Equibar
    • LMethyldopa
    • alphaMethylLdopa
    • LalphaMethyldopa
    • UNII-33TD13T99R
    • Methyl-dopa
    • 3-Hydroxy-.alpha.-methyl-L-tyrosine
    • Tyrosine, 3-hydroxy-.alpha.-methyl-
    • ()Methyldopa
    • .alpha.-Medopa
    • 3,4-Dihydroxy-2-methylphenylalanine #
    • L(alphaMd)
    • Methyldopa dl-form
    • .alpha.-Methyldopa
    • L-a-Methyl-DOPA
    • .alpha.-Methyl-L-3,4-dihydroxyphenylalanine
    • D-?-Methyl DOPA
    • DL-Tyrosine, 3-hydroxy-alpha-methyl-
    • rac ?-Methyl DOPA
    • DL-alpha-Methyl-DOPA
    • ? METHYLDOPA
    • rac alpha -Methyl DOPA
    • Alanine, 3-(3,4-dihydroxyphenyl)-2-methyl-, L-
    • CHEMBL718
    • 2-Methyl-3-(3,4-dihydroxyphenyl)-DL-alanine
    • 3HydroxyalphamethylLtyrosine
    • Lopac0_000770
    • SCHEMBL196981
    • WLN: QVXZ1&1R CQ DQ
    • METHYLDOPA DL-FORM [MI]
    • ALANINE, 3-(3,4-DIHYDROXYPHENYL)-2-METHYL-, DL-
    • DTXSID50859484
    • DTXSID60970356
    • CHEBI:180994
    • HMS3259C21
    • HMS3262I22
    • HMS3266O08
    • AAA55530
    • ALBB-024010
    • BCP28393
    • CAA79915
    • Tox21_500770
    • (+/-)-.ALPHA.-METHYLDOPA
    • alphaMethylL3,4dihydroxyphenylalanine
    • LalphaMethyl3,4dihydroxyphenylalanine
    • 3(3,4Dihydroxyphenyl)2methylLalanine
    • AKOS003273681
    • AKOS017258656
    • AC-8433
    • CCG-204855
    • LP00770
    • NC00520
    • SDCCGSBI-0050748.P005
    • L()3(3,4Dihydroxyphenyl)2methylalanine
    • NCGC00015631-03
    • NCGC00015631-04
    • NCGC00015631-05
    • NCGC00015631-09
    • NCGC00094109-01
    • NCGC00094109-02
    • NCGC00261455-01
    • AC-11788
    • SBI-0050748.P004
    • 3-Hydroxy-alpha-methyltyrosine sesquihydrate
    • Alanine,4-dihydroxyphenyl)-2-methyl-, L-
    • alpha-methyl-3,4-dihydroxy-dl-phenylalanine
    • alphaMethylbeta(3,4dihydroxyphenyl)Lalanine
    • DB-018032
    • DB-052752
    • EU-0100770
    • NS00079124
    • L()alphaMethylbeta(3,4dihydroxyphenyl)alanine
    • L()beta(3,4Dihydroxyphenyl)alphamethylalanine
    • 2-(3,4-dihydroxybenzyl)-2-aminopropanoic acid
    • 3-(3,4-dihydroxyphenyl)-2-methyl-DL-alanine
    • EN300-297472
    • H34296
    • M 7277
    • Alanine,4-dihydroxyphenyl)-2-methyl-, L-(-)-
    • alpha-Methyl-DL-beta-3,4-Dihydroxyphenylalanine
    • L001029
    • L2Amino2methyl3(3,4dihydroxyphenyl)propionic acid
    • L2Amino3(3,4dihydroxyphenyl)2methylpropionic acid
    • SR-01000076007

  • Applications

    Alpha-methyldopa, CAS 55-40-3, is primarily encountered in pharmaceutical manufacturing as an active pharmaceutical ingredient in antihypertensive formulations and as an intermediate for the synthesis of related catecholamine derivatives; it also appears in research settings to study adrenergic metabolism and neurotransmitter pathways, and can be used as a reference material or calibration standard in analytical laboratories. In addition, it serves in industrial and formulation development as an organic synthesis building block, with handling and use governed by applicable regulations.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 0.25
    methanol 1.15
    isopropanol 0.2
    water 3.14
    ethyl acetate 0.49
    n-propanol 0.09
    acetone 0.34
    n-butanol 0.09
    acetonitrile 0.07
    DMF 1.15
    toluene 0.17
    isobutanol 0.11
    1,4-dioxane 0.35
    methyl acetate 0.15
    THF 1.61
    2-butanone 0.2
    n-pentanol 0.11
    sec-butanol 0.19
    n-hexane 0.03
    ethylene glycol 4.75
    NMP 16.48
    cyclohexane 0.04
    DMSO 7.22
    n-butyl acetate 0.33
    n-octanol 0.23
    chloroform 0.02
    n-propyl acetate 0.17
    acetic acid 4.68
    dichloromethane 0.02
    cyclohexanone 0.5
    propylene glycol 2.48
    isopropyl acetate 0.62
    DMAc 7.81
    2-ethoxyethanol 4.08
    isopentanol 0.32
    n-heptane 0.13
    ethyl formate 0.25
    1,2-dichloroethane 0.02
    n-hexanol 0.45
    2-methoxyethanol 6.78
    isobutyl acetate 0.09
    tetrachloromethane 0.07
    n-pentyl acetate 0.26
    transcutol 6.68
    n-heptanol 0.53
    ethylbenzene 0.18
    MIBK 0.88
    2-propoxyethanol 4.41
    tert-butanol 1.93
    MTBE 0.4
    2-butoxyethanol 2.26
    propionic acid 0.57
    o-xylene 0.45
    formic acid 39.93
    diethyl ether 0.13
    m-xylene 0.48
    p-xylene 0.17
    chlorobenzene 0.04
    dimethyl carbonate 0.86
    n-octane 0.05
    formamide 20.9
    cyclopentanone 1.1
    2-pentanone 0.42
    anisole 0.48
    cyclopentyl methyl ether 0.9
    gamma-butyrolactone 2.14
    1-methoxy-2-propanol 5.12
    pyridine 0.19
    3-pentanone 0.24
    furfural 3.98
    n-dodecane 0.03
    diethylene glycol 14.68
    diisopropyl ether 0.26
    tert-amyl alcohol 1.59
    acetylacetone 2.63
    n-hexadecane 0.03
    acetophenone 0.99
    methyl propionate 0.47
    isopentyl acetate 0.5
    trichloroethylene 0.07
    n-nonanol 0.29
    cyclohexanol 0.32
    benzyl alcohol 0.58
    2-ethylhexanol 0.55
    isooctanol 0.6
    dipropyl ether 0.44
    1,2-dichlorobenzene 0.09
    ethyl lactate 1.45
    propylene carbonate 1.49
    n-methylformamide 0.73
    2-pentanol 0.22
    n-pentane 0.02
    1-propoxy-2-propanol 2.78
    1-methoxy-2-propyl acetate 2.17
    2-(2-methoxypropoxy) propanol 5.51
    mesitylene 0.51
    ε-caprolactone 0.88
    p-cymene 0.46
    epichlorohydrin 0.58
    1,1,1-trichloroethane 0.04
    2-aminoethanol 2.73
    morpholine-4-carbaldehyde 8.15
    sulfolane 12.16
    2,2,4-trimethylpentane 0.07
    2-methyltetrahydrofuran 0.74
    n-hexyl acetate 0.34
    isooctane 0.06
    2-(2-butoxyethoxy)ethanol 5.23
    sec-butyl acetate 0.22
    tert-butyl acetate 1.9
    decalin 0.06
    glycerin 20.2
    diglyme 7.31
    acrylic acid 1.26
    isopropyl myristate 0.25
    n-butyric acid 0.72
    acetyl acetate 0.67
    di(2-ethylhexyl) phthalate 0.78
    ethyl propionate 0.4
    nitromethane 3.12
    1,2-diethoxyethane 0.45
    benzonitrile 0.14
    trioctyl phosphate 0.51
    1-bromopropane 0.01
    gamma-valerolactone 3.43
    n-decanol 0.26
    triethyl phosphate 0.84
    4-methyl-2-pentanol 0.53
    propionitrile 0.04
    vinylene carbonate 0.68
    1,1,2-trichlorotrifluoroethane 5.33
    DMS 0.6
    cumene 0.27
    2-octanol 0.29
    2-hexanone 0.21
    octyl acetate 0.32
    limonene 0.52
    1,2-dimethoxyethane 2.41
    ethyl orthosilicate 0.76
    tributyl phosphate 0.42
    diacetone alcohol 8.04
    N,N-dimethylaniline 0.88
    acrylonitrile 0.08
    aniline 0.3
    1,3-propanediol 2.13
    bromobenzene 0.03
    dibromomethane 0.01
    1,1,2,2-tetrachloroethane 0.09
    2-methyl-cyclohexyl acetate 0.71
    tetrabutyl urea 0.97
    diisobutyl methanol 0.79
    2-phenylethanol 1.0
    styrene 0.11
    dioctyl adipate 0.47
    dimethyl sulfate 4.15
    ethyl butyrate 0.52
    methyl lactate 3.87
    butyl lactate 0.96
    diethyl carbonate 0.39
    propanediol butyl ether 2.9
    triethyl orthoformate 0.64
    p-tert-butyltoluene 0.54
    methyl 4-tert-butylbenzoate 3.71
    morpholine 0.47
    tert-butylamine 0.58
    n-dodecanol 0.22
    dimethoxymethane 1.93
    ethylene carbonate 0.39
    cyrene 11.67
    2-ethoxyethyl acetate 0.7
    2-ethylhexyl acetate 0.31
    1,2,4-trichlorobenzene 0.16
    4-methylpyridine 0.2
    dibutyl ether 0.13
    2,6-dimethyl-4-heptanol 0.79
    DEF 0.89
    dimethyl isosorbide 10.8
    tetrachloroethylene 0.19
    eugenol 3.84
    triacetin 1.36
    span 80 3.35
    1,4-butanediol 0.91
    1,1-dichloroethane 0.01
    2-methyl-1-pentanol 0.32
    methyl formate 0.85
    2-methyl-1-butanol 0.24
    n-decane 0.04
    butyronitrile 0.04
    3,7-dimethyl-1-octanol 0.4
    1-chlorooctane 0.07
    1-chlorotetradecane 0.05
    n-nonane 0.04
    undecane 0.03
    tert-butylcyclohexane 0.07
    cyclooctane 0.05
    cyclopentanol 0.36
    tetrahydropyran 0.1
    tert-amyl methyl ether 0.76
    2,5,8-trioxanonane 8.92
    1-hexene 0.04
    2-isopropoxyethanol 2.27
    2,2,2-trifluoroethanol 4.06
    methyl butyrate 0.4

    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