Cytosine

• Formula: C₄H₅N₃O
• Molecular weight: 111.1020
• IUPAC Standard InChI: InChI=1S/C4H5N3O/c5-3-1-2-6-4(8)7-3/h1-2H,(H3,5,6,7,8) Copy

  
• IUPAC Standard InChIKey: OPTASPLRGRRNAP-UHFFFAOYSA-N Copy
• CAS Registry Number: 71-30-7
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: 2(1H)-Pyrimidinone, 4-amino-; Cyt; Cytosinimine; 4-Amino-2(1H)-pyrimidinone; 4-Amino-2-hydroxypyrimidine; 4-Amino-2(1H)pyrimidone; 4-Amino-2-oxypyrimidine
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
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Gas phase thermochemistry 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Condensed phase thermochemistry 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of solid

Reaction thermochemistry 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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C₄H₆N₃O⁺ +  = (C₄H₆N₃O⁺ • )

By formula: C₄H₆N₃O⁺ + C₄H₅N₃O = (C₄H₆N₃O⁺ • C₄H₅N₃O)

 +  = ( • )

By formula: Na⁺ + C₄H₅N₃O = (Na⁺ • C₄H₅N₃O)

 +  = ( • )

By formula: K⁺ + C₄H₅N₃O = (K⁺ • C₄H₅N₃O)

References

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

Sabbah, 1980
Sabbah, R., Thermodynamics of nitrogen compounds. V. Thermochemical study of cytosine, Thermochim. Acta, 1980, 35, 73-77. [all data]

Wilson, Watson, et al., 1979
Wilson, S.R.; Watson, I.D.; Malcolm, G.N., Enthalpies of formation of solid cytosine, L-histidine, and uracil, J. Chem. Thermodyn., 1979, 11, 911-912. [all data]

Sabbah, Nabavian, et al., 1977
Sabbah, R.; Nabavian, M.; Laffitte, M., Sur l'enthalpie de formation de la cytosine a 1'etat solide., C. R. Acad. Sci. Paris, 1977, 284, 953-954. [all data]

Kilday, 1978
Kilday, M.V., Enthalpies of solution of the nucleic acid bases. 3. Cytosine in water, J. Res., 1978, NBS 83, 539-546. [all data]

Meot-Ner (Mautner), 1979
Meot-Ner (Mautner), M., Ion Thermochemistry of Low Volatility Compounds in the Gas Phase. II. Intrinsic Basicities and Hydrogen Bonded Dimers of Nitrogen Heterocyclics and Nucleic Bases, J. Am. Chem. Soc., 1979, 101, 9, 2396, https://doi.org/10.1021/ja00503a027 . [all data]

Cerda and Wesdemiotis, 1996
Cerda, B.A.; Wesdemiotis, C., PAs of Peptides, J. Am. Chem. Soc., 1996, 118, 11884. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, References

• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

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