L-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)/t9-/m1/s1 Copy

  
• IUPAC Standard InChIKey: QIVBCDIJIAJPQS-SECBINFHSA-N Copy
• CAS Registry Number: 73-22-3
• Chemical structure:
  This structure is also available as a 2d Mol file
• Stereoisomers:
  • Tryptophan
• Other names: Tryptophan, L-; L-α-amino-3-indolepropionic acid; Tryptophan; L-Tryptophane; α-Aminoindole-3-propionic acid; L-α-aminoindole-3-propionic acid; L-β-3-indolylalanine; EH 121; L-(-)-Tryptophan; L-Trp; Trp; Tryptophane; 1H-Indole-3-alanine; 1H-Indole-3-propanoic acid, α-amino-, (S)-; 2-Amino-3-indolylpropanoic acid; α'-Amino-3-indolepropionic acid; Alanine, 3-indol-3-yl-; Indole-3-alanine; Indole-3-propionic acid, α-amino-; NCI-C01729; Pacitron; Propionic acid, 2-amino-3-indol-3-yl-; L-Tryptofan; (S)-Tryptophan; (S)-α-Amino-1H-indole-3-propanoic acid; (-)-Tryptophan; 1H-Indole-3-alanine, (S)-; 3-Indol-3-ylalanine; L-Alanine, 3-(1H-indol-3-yl)-; NSC 13119
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• Information on this page:
  • Condensed phase thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • References
  • Notes
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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

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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias

Data compiled as indicated in comments:
MM - Michael M. Meot-Ner (Mautner)

Proton affinity at 298K

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• SOLID (1 mg / 200 mg KBr DISC); PERKIN-ELMER 21 (GRATING); DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY; 2 cm^-1 resolution
• SOLID (OIL MULL); PERKIN-ELMER 521 (GRATING); DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution

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, Condensed phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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.

Tsuzuki, Harper, et al., 1958
Tsuzuki, T.; Harper, D.O.; Hunt, H., Heats of combustion. VII. The heats of combustion of some amino acids, J. Phys. Chem., 1958, 62, 1594-1595. [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]

Cole, Hutchens, et al., 1963
Cole, A.G.; Hutchens, J.O.; Stout, J.W., Heat capacities from 11 to 305°K. and entropies of L-phenylalanine, L-proline, L-tryptophane, and L-tyrosine. Some free energies of formation, J. Phys. Chem., 1963, 67, 1852-1855. [all data]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Mirza, Prabhakar, et al., 2001
Mirza, S.P.; Prabhakar, S.; Vairamani, M., Estimation of proton affinity of proline and tryptophan under electrospray ionization conditions using the extended kinetic method, Rapid Comm. Mass Spectrometry, 2001, 15, 957. [all data]

Bojesen and Breindahl, 1994
Bojesen, G.; Breindahl, T., On the Proton Affinity od Some Alpha-Amino Acids and the Theory of the Kinetic Method., J. Chem. Soc. Perkin 2, 1994, 1029. [all data]

Notes

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• 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

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