Tryptophan

• Formula: C₁₁H₁₂N₂O₂
• Molecular weight: 204.2252
• IUPAC Standard InChI: InChI=1S/C11H12N2O2/c12-9(11(14)15)5-7-6-13-10-4-2-1-3-8(7)10/h1-4,6,9,13H,5,12H2,(H,14,15) Copy

  
• IUPAC Standard InChIKey: QIVBCDIJIAJPQS-UHFFFAOYSA-N Copy
• CAS Registry Number: 54-12-6
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Stereoisomers:
  • L-Tryptophan
• Other names: DL-Tryptophan; DL-α-Amino-3-indolepropionic acid; DL-Trytophan; DL-Trytophane; Racemic Tryptophan; Tryptophan, DL-; Tryptophane; (.+/-.)-Tryptophan; NSC 13118; DL-Tryptophane
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • UV/Visible spectrum
• Options:
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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:
B - John E. Bartmess
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

 +  =

By formula: C₁₁H₁₁N₂O₂^- + H⁺ = C₁₁H₁₂N₂O₂

 +  = ( • )

By formula: Na⁺ + C₁₁H₁₂N₂O₂ = (Na⁺ • C₁₁H₁₂N₂O₂)

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 as indicated in comments:
B - John E. Bartmess
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

De-protonation reactions

 +  =

By formula: C₁₁H₁₁N₂O₂^- + H⁺ = C₁₁H₁₂N₂O₂

Ion clustering 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: Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

 +  = ( • )

By formula: Na⁺ + C₁₁H₁₂N₂O₂ = (Na⁺ • C₁₁H₁₂N₂O₂)

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

References

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Notes

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

Jones, Bernier, et al., 2007
Jones, C.M.; Bernier, M.; Carson, E.; Colyer, K.E.; Metz, R.; Pawlow, A.; Wischow, E.D.; Webb, I.; Andriole, E.J.; Poutsma, J.C., Gas-phase Acities of the 20 Protein Amino Acids, Int. J. Mass Spectrom., 2007, 267, 1-3, 54-62, https://doi.org/10.1016/j.ijms.2007.02.018 . [all data]

O'Hair, Bowie, et al., 1992
O'Hair, R.J.; Bowie, J.H.; Gronert, S., Gas Phase Acidity of the alpha-Amino Acids, Int. J. Mass Spectrom. Ion Proc., 1992, 117, 23, https://doi.org/10.1016/0168-1176(92)80083-D . [all data]

Gapeev and Dunbar, 2003
Gapeev, A.; Dunbar, R.C., Na+ Affinities of Gas-Phase Amino Acids by Ligand Exchange Equilibrium, Int. J. Mass Spectrom., 2003, 228, 2-3, 825, https://doi.org/10.1016/S1387-3806(03)00242-2 . [all data]

Kish, Ohanessian, et al., 2003
Kish, M.M.; Ohanessian, G.; Wesdemiotis, C., The Na+ affinities of a-amino acids: side-chain substituent effects, Int. J. Mass Spectrom., 2003, 227, 3, 509, https://doi.org/10.1016/S1387-3806(03)00082-4 . [all data]

Slifkin and Allison, 1967
Slifkin, M.A.; Allison, A.C., Measurement of ionization potentials from contact charge transfer spectra, Nature, 1967, 215, 949. [all data]

Akopyan and Loginov, 1967
Akopyan, M.E.; Loginov, Yy.V., Mass-spectrometric study of the phoionization of free α-aminoacids, High Energy Chem., 1967, 1, 83, In original 97. [all data]

Notes

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• Symbols used in this document:
  

  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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