Acetaminophen

• Formula: C₈H₉NO₂
• Molecular weight: 151.1626
• IUPAC Standard InChI: InChI=1S/C8H9NO2/c1-6(10)9-7-2-4-8(11)5-3-7/h2-5,11H,1H3,(H,9,10) Copy

  
• IUPAC Standard InChIKey: RZVAJINKPMORJF-UHFFFAOYSA-N Copy
• CAS Registry Number: 103-90-2
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Other names: Acetamide, N-(4-hydroxyphenyl)-; Acetanilide, 4'-hydroxy-; p-(Acetylamino)phenol; p-Acetamidophenol; p-Hydroxyacetanilide; p-Hydroxyphenolacetamide; Abensanil; Acamol; Acetagesic; Acetalgin; Acetaminofen; Algotropyl; Alvedon; Amadil; Anaflon; Anelix; Apamid; Apamide; APAP; Ben-u-Ron; Bickie-mol; Calpol; Cetadol; Clixodyne; Dial-a-gesic; Dirox; Dymadon; Eneril; Febrilix; Febro-Gesic; Febrolin; Fendon; Finimal; Hedex; Homoolan; Lestemp; Liquagesic; Lonarid; Lyteca; Lyteca Syrup; Multin; N-(4-Hydroxyphenyl)acetamide; N-Acetyl-p-aminophenol; N-Acetyl-4-aminophenol; Napafen; Naprinol; Nobedon; NAPA; NAPAP; Pacemo; Panadol; Panets; Paracetamol; Paracetamole; Paracetanol; Parmol; Pedric; Phendon; Pyrinazine; Tabalgin; Temlo; Tempanal; Tempra; Tralgon; Tussapap; Tylenol; Valadol; Valgesic; 4-Acetamidophenol; 4-Acetaminophenol; 4-Hydroxyacetanilide; 4'-Hydroxyacetanilide; Accu-Tap; Acetamide, N-(p-hydroxyphenyl)-; Alpiny; Anapap; Anhiba; Apadon; Datril; Dimindol; Dularin; Dypap; Elixodyne; Febridol; Febrinol; G 1; Gelocatil; Injectapap; Janupap; Korum; Nealgyl; Nebs; Neotrend; NCI-C55801; Painex; Paracet; Paracetamol DC; Parapan; Phenol, p-acetamido-; Rivalgyl; Servigesic; St. Joseph Fever Reducer; SK-Apap; Tapar; Alpinyl; Doliprane; Enelfa; Exdol; 4-Hydroxyanilid kyseliny octove; Momentum; Panex; Panofen; Paracetamolo; Paraspen; Banesin; Phenaphen; Captin; Dafalgan; Disprol; Dolprone; Eu-Med; Ortensan; Paldesic; Panaleve; Panasorb; Parelan; Pasolind N; Salzone; 4-(Acetylamino)phenol; 4-(N-Acetylamino)phenol; Acenol; Biocetamol; Citramon P; Claratal; Cyclopam; Daga; Daphalgan; Minoset; N-Acetyl-4-hydroxyaniline; Pacemol; Panodil; Pinex; Pyral; Resfenol; Resprin; Vermidon; p-Acetoaminophen; N-(p-Hydroxyphenyl) acetamide; Actifed Plus (Salt/Mix); Anexsia (Salt/Mix); Aspirin-Free Anacin (Salt/Mix); Bayer Select Allergy-Sinus (Salt/Mix); Bayer Select Head Cold (Salt/Mix); Bayer Select Menstrual Multi-Symptom (Salt/Mix); Bayer Select Sinus Pain Relief (Salt/Mix); Contac Cough & Sore Throat Formula (Salt/Mix); Coricidin (Salt/Mix); Coricidin D (Salt/Mix); Coricidin Sinus (Salt/Mix); DHCplus (Salt/Mix); Darvocet-N (Salt/Mix); Demilets (Salt/Mix); Drixoral Cold & Flu (Salt/Mix); Drixoral Sinus (Salt/Mix); Empracet (Salt/Mix); Endecon (Salt/Mix); Hy-Phen (Salt/Mix); Hycomine Compound (Salt/Mix); Intensin (Salt/Mix); Liquiprin (Salt/Mix); Midol Maximum Strength (Salt/Mix); Midol PM Night Time Formula (Salt/Mix); Midol Regular Strength (Salt/Mix); Midol Teen Formula (Salt/Mix); Naldegesic (Salt/Mix); Ornex Severe Cold Formula (Salt/Mix); Percocet (Salt/Mix); Propacet (Salt/Mix); Quiet World (Salt/Mix); Rhinex D-Lay Tablets (Salt/Mix); Robitussin Night Relief (Salt/Mix); Sine-Aid, Maximum Strength (Salt/Mix); Sine-Off Sinus Medicine Caplets (Salt/Mix); Sinubid (Salt/Mix); St. Joseph Cold Tablets for Children (Salt/Mix); Sudafed Cold and Cough (Salt/Mix); Sudafed Severe Cold Formula (Salt/Mix); Sudafed Sinus (Salt/Mix); Supac (Salt/Mix); Talacen (Salt/Mix); TheraFlu (Salt/Mix); Triaminic Sore Throat Formula (Salt/Mix); Tylenol Allergy Sinus (Salt/Mix); Tylox (Salt/Mix); Vanquish (Salt/Mix); Vicodin (Salt/Mix); Zydone (Salt/Mix); Wygesic (Salt/Mix)
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• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • IR Spectrum
  • THz IR spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
  • References
  • Notes
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Phase change data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Enthalpy of fusion

Gas phase ion energetics data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

Appearance energy determinations

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• SOLID (NUJOL MULL); PERKIN-ELMER 21 (GRATING) $$SPECTRAL CONTAMINATION DUE TO OIL AROUND 2850 CM^-1; 2 cm^-1 resolution

Data compiled by: Timothy J. Johnson, Tanya L. Myers, Yin-Fong Su, Russell G. Tonkyn, Molly Rose K. Kelly-Gorham, and Tyler O. Danby

• solid; Bruker Tensor 37 FTIR; 0.96450084 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas; HP-GC/MS/IRD

THz IR spectrum

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Edwin J. Heilweil and Matthew B. Campbell

Condensed Phase Spectrum

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Additional Data

Mass spectrum (electron ionization)

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

UV/Visible spectrum

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

Gas Chromatography

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Kovats' RI, non-polar column, isothermal

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Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Van Den Dool and Kratz RI, non-polar column, custom temperature program

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Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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References

Go To: Top, Phase change data, Gas phase ion energetics data, IR Spectrum, THz IR spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Gas Chromatography, NIST Subscription Links, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Manzo and Ahumanda, 1990
Manzo, R.H.; Ahumanda, A.A., Effects of solvent medium on solubility. V: Enthalpic and entropic contributions to the free energy changes of Di-substituted benzene derivatives in ethanol: Water and ethanol: Cyclohexane mixtures, J. Pharm. Sci., 1990, 79, 12, 1109, https://doi.org/10.1002/jps.2600791214 . [all data]

El-Banna, 1978
El-Banna, H.M., Solid Dispersion of Pharmaceutaical Ternary Systems I. Phase Diagrams of Aspirin- Acetominophen-Urea Systems, J. Pharm. Sci., 1978, 67, 1109. [all data]

Vecchio and Tomassetti, 2009
Vecchio, Stefano; Tomassetti, Mauro, Vapor pressures and standard molar enthalpies, entropies and Gibbs energies of sublimation of three 4-substituted acetanilide derivatives, Fluid Phase Equilibria, 2009, 279, 1, 64-72, https://doi.org/10.1016/j.fluid.2009.02.001 . [all data]

Mota, Carneiro, et al., 2009
Mota, Fátima L.; Carneiro, Aristides P.; Queimada, António J.; Pinho, Simão P.; Macedo, Eugénia A., Temperature and solvent effects in the solubility of some pharmaceutical compounds: Measurements and modeling, European Journal of Pharmaceutical Sciences, 2009, 37, 3-4, 499-507, https://doi.org/10.1016/j.ejps.2009.04.009 . [all data]

Xu, Sun, et al., 2006
Xu, F.; Sun, L.X.; Tan, Z.C.; Liang, J.G.; Zhang, T., Adiabatic calorimetry and thermal analysis on acetaminophen, J Therm Anal Calorim, 2006, 83, 1, 187-191, https://doi.org/10.1007/s10973-005-6969-0 . [all data]

Romero, Bustamante, et al., 2004
Romero, S.; Bustamante, P.; Escalera, B.; Cirri, M.; Mura, P., Characterization of the solid phases of paracetamol and fenamates at equilibrium in saturated solutions, Journal of Thermal Analysis and Calorimetry, 2004, 77, 2, 541-554, https://doi.org/10.1023/B:JTAN.0000038993.61782.ba . [all data]

Manzo and Ahumada, 1990
Manzo, Ruben H.; Ahumada, Amelia A., Effects of solvent medium on solubility. V: Enthalpic and entropic contributions to the free energy changes of Di-substituted benzene derivatives in ethanol: Water and ethanol: Cyclohexane mixtures, J. Pharm. Sci., 1990, 79, 12, 1109-1115, https://doi.org/10.1002/jps.2600791214 . [all data]

Benezra and Bursey, 1972
Benezra, S.A.; Bursey, M.M., Hydrogen bonding in mass spectral activated complexes. A correction, J. Chem. Soc. Perkin Trans. 2, 1972, 11, 1537. [all data]

Lang (editor), 1965
Lang (editor), L., Absorption Spectra in the Ultraviolet and Visible Region, 1965, 5, 93. [all data]

Phillips, Logan, et al., 1990
Phillips, A.M.; Logan, B.K.; Stafford, D.T., Further applications for capillary gas chromatography in routine quantitative toxicological analyses, J. Hi. Res. Chromatogr., 1990, 13, 11, 754-758, https://doi.org/10.1002/jhrc.1240131106 . [all data]

Japp, Gill, et al., 1987
Japp, M.; Gill, R.; Osselton, M.D., Comparison of drug retention indices determined on packed, wide bore capillary and narrow bore capillary columns, J. Forensic Sci., 1987, 32, 6, 1574-1586. [all data]

Lora-Tamayo, Rams, et al., 1986
Lora-Tamayo, C.; Rams, M.A.; Chacon, J.M.R., Gas Chromatographic Data for 187 Nitrogen- or Phosphorus-Containing Drugs and Metabolites of Toxicological Interest Analysed on Methyl Silicone Capillary Columns, J. Chromatogr., 1986, 374, 73-85, https://doi.org/10.1016/S0378-4347(00)83254-5 . [all data]

Möller, 1976
Möller, M.R., Comparability of retention indices of polar substances at elevated temperatures, Chromatographia, 1976, 9, 7, 311-314, https://doi.org/10.1007/BF02268832 . [all data]

Christ, Noomano, et al., 1988
Christ, D.W.; Noomano, P.; Rosas, M.; Rhone, D., Retention indices by wide-bore capillary gas chromatography with nitrogen-phosphorus detection, J. Anal. Toxicol., 1988, 12, 2, 84-88, https://doi.org/10.1093/jat/12.2.84 . [all data]

Perrigo, Peel, et al., 1985
Perrigo, B.J.; Peel, H.W.; Ballantyne, D.J., Use of Dual-Column Fused-Silica Capillary Gas Chromatography in Combination with Detector Response Factors for Analytical Toxicology., J. Chromatogr., 1985, 341, 81-88, https://doi.org/10.1016/S0378-4347(00)84011-6 . [all data]

Newton and Foery, 1984
Newton, B.; Foery, R.F., Retention indices and dual capillary gas chromatography for rapid identification of sedative hypnotic drugs in emergency toxicology, J. Anal. Toxicol., 1984, 8, 3, 129-134, https://doi.org/10.1093/jat/8.3.129 . [all data]

Perrigo, Ballantyne, et al., 1984
Perrigo, B.J.; Ballantyne, D.J.; Peel, H.W., Condierations in developing a data base for drugs on a DBI capillary column, J. Can. Soc. Forensic Sci., 1984, 17, 2, 41-49, https://doi.org/10.1080/00085030.1984.10757360 . [all data]

Stowell and Wilson, 1987
Stowell, A.; Wilson, L.W., A simple approach to the interlaboratory transfer of drug retention indices determined by temperature programmed capillary gas chromatography, J. Forensic Sci., 1987, 32, 5, 1214-1220. [all data]

Boustie, Rapior, et al., 2005
Boustie, J.; Rapior, S.; Fortin, H.; Tomas, S.; Bessiere, J.-M., Chemotaxonomic interest of volatile components in Lepista inversa and Lepista flaccida distinctions, Cryptogamie, Mycologie, 2005, 26, 1, 1-4. [all data]

Stowell and Wilson, 1985
Stowell, A.; Wilson, L., Use of retention indices in drug screening by capillary gas chromatography, Rep. # CD 2362, Department of Scientific and Industrial Reseach, Chemistry Division, Lower Hutt, NZ, 1985, 32. [all data]

Ardrey and Moffat, 1981
Ardrey, R.E.; Moffat, A.C., Gas-liquid chromatographic retention indices of 1318 substances of toxicological interest on SE-30 or OV-1 stationary phase, J. Chromatogr., 1981, 220, 3, 195-252, https://doi.org/10.1016/S0021-9673(00)81925-1 . [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Tfus	Fusion (melting) point
  ΔfusH	Enthalpy of fusion
  ΔsubH°	Enthalpy of sublimation at standard conditions
  ΔvapH	Enthalpy of vaporization

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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