Cystine

• Formula: C₆H₁₂N₂O₄S₂
• Molecular weight: 240.300
• IUPAC Standard InChI: InChI=1S/C6H12N2O4S2/c7-3(5(9)10)1-13-14-2-4(8)6(11)12/h3-4H,1-2,7-8H2,(H,9,10)(H,11,12)/t3-,4-/m1/s1 Copy

  
• IUPAC Standard InChIKey: LEVWYRKDKASIDU-QWWZWVQMSA-N Copy
• CAS Registry Number: 56-89-3
• Chemical structure:
  This structure is also available as a 2d Mol file
• Stereoisomers:
  • DL-Cystine
• Other names: l-Cystine; β,β'-Diamino-β,β'-dicarboxydiethyl disulfide; β,β'-Dithiodialanine; Alanine, 3,3'-dithiobis-; Alanine, 3,3'-dithiodi-; Bis(β-amino-β-carboxyethyl) disulfide; Cysteine disulfide; Cystin; Cystine acid; Cystine, L-; Dicysteine; Oxidized L-cysteine; Propanoic acid, 3,3'-dithiobis(2-amino-, (R-(R*,R*))-; 3,3'-Dithiobis(2-aminopropanoic acid); 3,3'-Dithiodialanine; β,β'-Dithiobisalanine; 3,3'-Dithiobis(2-aminopropionic acid); L-3,3'-dithiodialanine; (R-(R*,R*))-3,3'-Dithiobis(2-aminopropanoic acid); (-)-Cystine; L-Alanine, 3,3'-dithiobis-; L-Cysteine disulfide; L-Cystin; NSC 13203
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Condensed phase thermochemistry data
  • References
  • Notes
• Other data available:
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
• Data at other public NIST sites:
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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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

References

Go To: Top, Condensed phase thermochemistry data, Notes

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

Becker and Roth, 1934
Becker, G.; Roth, W.A., Zur bestimmung der verbrennungswarme von organischen schwefelverbindunge, Z. Phys. Chem., 1934, 169, 287-296. [all data]

Sunner, 1946
Sunner, S., Determination of combustion heats of organo-sulphur compounds, Svensk. Kim. Tidr., 1946, 58, 71-81. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Huffman and Ellis, 1935
Huffman, H.M.; Ellis, E.L., Thermal Data. II. The heats of combustion of l-cysteine, of l-cystine, β-thiolactic acid and β,β'-dithiodilactic acid, J. Am. Chem. Soc., 1935, 57, 41-46. [all data]

Emery and Benedict, 1911
Emery, A.G.; Benedict, F.G., The heat of combustion of compounds of physiological importance, Am. J. Physiol., 1911, 28, 301-307. [all data]

Hutchens, Cole, et al., 1964
Hutchens, J.O.; Cole, A.G.; Stout, J.W., Heat capacities and entropies of L-cystine and L-methionine. The transition of L-methionine near 305.5 K, J. Biol. Chem., 1964, 239, 591-595. [all data]

Huffman and Ellis, 1935, 2
Huffman, H.M.; Ellis, E.L., Thermal data. III. The heat capacities, entropies and free energies of four organic compounds containing sulfur, J. Am. Chem. Soc., 1935, 57, 46-48. [all data]

Notes

Go To: Top, Condensed phase thermochemistry data, References

• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions

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