Acetaminophen

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  • Identifiers

    CAS number
    103-90-2

    Molecular formula
    C8H9NO2

    SMILES
    CC(=O)NC1=CC=C(C=C1)O

    Safety labels

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Fruity 42.17%
    Meaty 41.18%
    Odorless 32.92%
    Savory 31.51%
    Burnt 31.36%
    Grape 29.76%
    Sweet 29.56%
    Roasted 28.35%
    Cooked 27.08%
    Bitter 26.79%

     

    Flavor
    Mild 45.94%
    Odorless 39.64%
    Phenolic 35.44%
    Fruity 31.93%
    Nutty 28.31%
    Sour 24.99%
    Musty 24.39%
    Powdery 22.66%
    Sweet 22.35%
    Orange flower 21.71%

     

    Odor impact est.
    Low

  • Properties

    XLogP3-AA
    0.5

    pKa est.
    9.36 (weak base)

    Molecular weight
    151.16 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra slow

    Melting point expt.

    • 336 to 342 °F (NTP, 1992)
    • 168-172
    • 168 °C
    • MP: 169-170.5 °C
    • 170 °C
    • 169-170 °C

    Boiling point

    • >500
    • >500 °C

    Flash point

    • 163.0 ˚C est.

    Solubility expt.

    • >22.7 [ug/mL] (The mean of the results at pH 7.4)
    • 1 to 5 mg/mL at 72 °F (NTP, 1992)
    • very slightly soluble in cold water but greater solubility in hot water
    • In water, 14,000 mg/L at 25 °C
    • Very slightly soluble in cold water, soluble in boiling water
    • Freely soluble in alcohol; soluble in methanol, ethanol, dimethylformamide, ethylene dichloride, acetone, ethyl acetate; slightly soluble in ether; practically insoluble in petroleum ether, pentane, benzene
    • 14 mg/mL at 25 °C
    • Solubility in water, g/100ml at 20 °C: 1.4 (moderate)

  • Synonyms

    • acetaminophen
    • Paracetamol
    • 4-Acetamidophenol
    • 103-90-2
    • Tylenol
    • N-(4-Hydroxyphenyl)acetamide
    • APAP
    • Panadol
    • N-Acetyl-p-aminophenol
    • 4'-Hydroxyacetanilide
    • Acetaminofen
    • Datril
    • p-Acetamidophenol
    • p-Hydroxyacetanilide
    • Algotropyl
    • Doliprane
    • Injectapap
    • Lonarid
    • Naprinol
    • Acenol
    • Biocetamol
    • Febridol
    • Servigesic
    • Vermidon
    • Acamol
    • Alpiny
    • Anelix
    • Multin
    • Neopap
    • Paracet
    • p-Acetaminophenol
    • Abensanil
    • Acetagesic
    • Acetalgin
    • Clixodyne
    • Gelocatil
    • Liquagesic
    • Pyrinazine
    • Acephen
    • Alvedon
    • Anaflon
    • Apamide
    • Dafalgan
    • Disprol
    • Dolprone
    • Dymadon
    • Febrilix
    • Febrolin
    • Finimal
    • Homoolan
    • Lestemp
    • Ortensan
    • Paldesic
    • Salzone
    • Tabalgin
    • Tralgon
    • Tussapap
    • Valadol
    • Valgesic
    • Amadil
    • Anhiba
    • Calpol
    • Captin
    • Dirox
    • Eneril
    • Fendon
    • Hedex
    • Lyteca
    • Pacemo
    • Panets
    • Parmol
    • Tapar
    • Tempra
    • Acetamide, N-(4-hydroxyphenyl)-
    • Paracetamolo
    • Paracetamolum
    • Dolgesic
    • Febrectal
    • Momentum
    • Abenol
    • Apacet
    • Banesin
    • Enelfa
    • Fensum
    • Minoset
    • Neodol
    • Pacemol
    • Panodil
    • Rounox
    • Suppap
    • Exdol
    • Pinex
    • p-Acetylaminophenol
    • 4-(Acetylamino)phenol
    • Febro-Gesic
    • NEBS
    • Acetamol
    • Acetofen
    • Aferadol
    • Algesidal
    • Apitrelal
    • Atralidon
    • Bacetamol
    • Calmanticold
    • Causalon
    • Codabrol
    • Codalgin
    • Codapane
    • Codoliprane
    • Cosutone
    • Custodial
    • Deminofen
    • Demogripal
    • Desfebre
    • Dolegrippin
    • Dolofugin
    • Doloreduct
    • Dolorfug
    • Dolorstop
    • Dorocoff
    • Dristancito
    • Duracetamol
    • Ecosetol
    • Elixodyne
    • Excipain
    • Fanalgic
    • Farmadol
    • Febranine

  • Applications

    Acetaminophen (CAS number: 103-90-2) is primarily used as the active pharmaceutical ingredient in over-the-counter and prescription medicines, formulated in tablets and liquids; it also serves as a chemical intermediate for the synthesis of related pharmaceutical compounds; in quality-control laboratories it functions as an analytical reference standard (for example in HPLC methods); and it is used in research and development as a model compound to study acetylation and amide formation, or as a reagent in method development, all subject to local regulations and formulation limits.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 132.9
    methanol 204.26
    isopropanol 81.9
    water 18.52
    ethyl acetate 16.17
    n-propanol 80.79
    acetone 74.56
    n-butanol 61.09
    acetonitrile 24.19
    DMF 281.06
    toluene 0.95
    isobutanol 42.82
    1,4-dioxane 23.7
    methyl acetate 35.39
    THF 71.62
    2-butanone 56.06
    n-pentanol 39.0
    sec-butanol 59.42
    n-hexane 1.25
    ethylene glycol 96.62
    NMP 171.8
    cyclohexane 0.23
    DMSO 335.27
    n-butyl acetate 15.17
    n-octanol 12.8
    chloroform 6.65
    n-propyl acetate 13.54
    acetic acid 65.39
    dichloromethane 6.97
    cyclohexanone 28.09
    propylene glycol 110.63
    isopropyl acetate 9.83
    DMAc 287.88
    2-ethoxyethanol 95.65
    isopentanol 38.02
    n-heptane 0.69
    ethyl formate 29.06
    1,2-dichloroethane 6.62
    n-hexanol 23.39
    2-methoxyethanol 175.64
    isobutyl acetate 7.42
    tetrachloromethane 3.28
    n-pentyl acetate 9.04
    transcutol 141.02
    n-heptanol 10.75
    ethylbenzene 2.01
    MIBK 14.56
    2-propoxyethanol 65.2
    tert-butanol 71.02
    MTBE 26.51
    2-butoxyethanol 30.84
    propionic acid 58.16
    o-xylene 2.29
    formic acid 117.94
    diethyl ether 15.83
    m-xylene 1.51
    p-xylene 2.76
    chlorobenzene 2.63
    dimethyl carbonate 19.37
    n-octane 0.27
    formamide 144.78
    cyclopentanone 55.69
    2-pentanone 26.61
    anisole 15.79
    cyclopentyl methyl ether 16.14
    gamma-butyrolactone 62.79
    1-methoxy-2-propanol 98.8
    pyridine 13.6
    3-pentanone 18.64
    furfural 64.7
    n-dodecane 0.25
    diethylene glycol 88.72
    diisopropyl ether 3.55
    tert-amyl alcohol 60.75
    acetylacetone 25.08
    n-hexadecane 0.28
    acetophenone 17.91
    methyl propionate 24.76
    isopentyl acetate 14.81
    trichloroethylene 12.58
    n-nonanol 10.2
    cyclohexanol 16.18
    benzyl alcohol 18.85
    2-ethylhexanol 10.72
    isooctanol 8.24
    dipropyl ether 7.92
    1,2-dichlorobenzene 4.23
    ethyl lactate 19.64
    propylene carbonate 30.65
    n-methylformamide 144.35
    2-pentanol 27.37
    n-pentane 0.71
    1-propoxy-2-propanol 39.04
    1-methoxy-2-propyl acetate 24.08
    2-(2-methoxypropoxy) propanol 46.92
    mesitylene 1.27
    ε-caprolactone 30.06
    p-cymene 3.08
    epichlorohydrin 52.43
    1,1,1-trichloroethane 6.24
    2-aminoethanol 127.23
    morpholine-4-carbaldehyde 104.39
    sulfolane 110.6
    2,2,4-trimethylpentane 0.85
    2-methyltetrahydrofuran 39.25
    n-hexyl acetate 17.16
    isooctane 0.43
    2-(2-butoxyethoxy)ethanol 52.04
    sec-butyl acetate 8.36
    tert-butyl acetate 13.92
    decalin 0.54
    glycerin 159.66
    diglyme 81.53
    acrylic acid 59.05
    isopropyl myristate 5.56
    n-butyric acid 39.09
    acetyl acetate 9.47
    di(2-ethylhexyl) phthalate 10.46
    ethyl propionate 12.7
    nitromethane 107.4
    1,2-diethoxyethane 18.0
    benzonitrile 10.15
    trioctyl phosphate 7.21
    1-bromopropane 4.23
    gamma-valerolactone 73.47
    n-decanol 7.06
    triethyl phosphate 11.06
    4-methyl-2-pentanol 12.63
    propionitrile 18.73
    vinylene carbonate 23.17
    1,1,2-trichlorotrifluoroethane 74.84
    DMS 15.71
    cumene 2.62
    2-octanol 7.26
    2-hexanone 21.91
    octyl acetate 8.48
    limonene 4.08
    1,2-dimethoxyethane 94.24
    ethyl orthosilicate 9.7
    tributyl phosphate 9.58
    diacetone alcohol 39.23
    N,N-dimethylaniline 13.83
    acrylonitrile 25.37
    aniline 9.2
    1,3-propanediol 110.37
    bromobenzene 1.49
    dibromomethane 4.21
    1,1,2,2-tetrachloroethane 12.16
    2-methyl-cyclohexyl acetate 12.27
    tetrabutyl urea 14.1
    diisobutyl methanol 6.16
    2-phenylethanol 15.96
    styrene 1.89
    dioctyl adipate 10.93
    dimethyl sulfate 52.35
    ethyl butyrate 11.36
    methyl lactate 39.41
    butyl lactate 17.99
    diethyl carbonate 9.88
    propanediol butyl ether 49.74
    triethyl orthoformate 10.79
    p-tert-butyltoluene 2.98
    methyl 4-tert-butylbenzoate 21.53
    morpholine 49.43
    tert-butylamine 26.65
    n-dodecanol 4.73
    dimethoxymethane 65.27
    ethylene carbonate 17.34
    cyrene 43.11
    2-ethoxyethyl acetate 16.35
    2-ethylhexyl acetate 11.39
    1,2,4-trichlorobenzene 7.2
    4-methylpyridine 16.38
    dibutyl ether 7.05
    2,6-dimethyl-4-heptanol 6.16
    DEF 41.64
    dimethyl isosorbide 54.85
    tetrachloroethylene 9.49
    eugenol 27.41
    triacetin 19.95
    span 80 27.64
    1,4-butanediol 53.41
    1,1-dichloroethane 5.64
    2-methyl-1-pentanol 28.31
    methyl formate 80.18
    2-methyl-1-butanol 41.1
    n-decane 0.49
    butyronitrile 17.81
    3,7-dimethyl-1-octanol 11.47
    1-chlorooctane 2.62
    1-chlorotetradecane 0.92
    n-nonane 0.45
    undecane 0.34
    tert-butylcyclohexane 0.77
    cyclooctane 0.13
    cyclopentanol 31.16
    tetrahydropyran 16.17
    tert-amyl methyl ether 22.75
    2,5,8-trioxanonane 58.95
    1-hexene 4.49
    2-isopropoxyethanol 47.86
    2,2,2-trifluoroethanol 42.87
    methyl butyrate 19.37

    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