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)
- IUPAC Standard InChIKey: QIVBCDIJIAJPQS-UHFFFAOYSA-N
- 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
The 3d structure may be viewed using Java or Javascript. - Stereoisomers:
- Other names: DL-Tryptophan; DL-α-Amino-3-indolepropionic acid; DL-Trytophan; DL-Trytophane; Racemic Tryptophan; Tryptophan, DL-; Tryptophane; (.+/-.)-Tryptophan; NSC 13118; DL-Tryptophane
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Gas phase ion energetics data
Go To: Top, References, Notes
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
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 8.43 | CTS | Slifkin and Allison, 1967 | RDSH |
| ≤7.5 | EI | Akopyan and Loginov, 1967 | RDSH |
De-protonation reactions
+
=
By formula: C11H11N2O2- + H+ = C11H12N2O2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 339.6 ± 2.2 | kcal/mol | CIDC | Jones, Bernier, et al., 2007 | gas phase; B |
| ΔrH° | 336.7 ± 3.1 | kcal/mol | G+TS | O'Hair, Bowie, et al., 1992 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 329.9 ± 3.0 | kcal/mol | CIDC | O'Hair, Bowie, et al., 1992 | gas phase; B |
References
Go To: Top, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
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]
Notes
Go To: Top, Gas phase ion energetics data, References
- 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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