Inokuchi Yoshiya, Kobayashi Yusuke, Ito Takafumi, Ebata Takayuki
Department of Chemistry, Faculty of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.
J Phys Chem A. 2007 May 3;111(17):3209-15. doi: 10.1021/jp070163a. Epub 2007 Apr 11.
The laser-induced fluorescence spectrum of jet-cooled L-tyrosine exhibits more than 20 vibronic bands in the 35450-35750 cm(-1) region. We attribute these bands to eight conformers by using results of UV-UV hole-burning spectroscopy. These isomers are classified into four groups; each group consists of two rotational isomers that have a similar side-chain conformation but different orientations of the phenolic OH. The splitting of band origins of rotational isomers is 31, 21, 5, and 0 cm(-1) for these groups. IR-UV spectra suggest that conformers belonging to two of the four groups have an intramolecular OH...N hydrogen bond between the COOH and NH2 groups. By comparing experimental and theoretical results of L-tyrosine with those of L-phenylalanine, we propose probable conformers of L-tyrosine.
