Chemical Properties
Off-White Crystalline Powder
Uses
A metabolite of Tryptophan (T947200).
Definition
ChEBI: 5-Hydroxytryptophol is a member of indoles.
Hazard
A reproductive hazard.
Biological Activity
5-hydroxy tryptophol is a metabolite of tryptophan.tryptophan (encoded by the codon ugg) is an α-amino acid that is used in the biosynthesis of proteins. tryptophan has an α-amino group, an α-carboxylic acid group, and a side chain indole, demonstrating it as a non-polar, aromatic amino acid. tryptophan is critical in humans, but the body cannot synthesize it and therefore tryptophan must be obtained from the diet. tryptophan is also found to be a precursor to the neurotransmitters serotonin and melatonin.
Synthesis
General procedure for the synthesis of 5-hydroxychromanol from 5-hydroxyindole-3-acetic acid:
1. 3-(2-hydroxyethyl)-1H-indole (F-3, 1.99 g, 52.3 mmol) and LiAlH4 (1.99 g, 52.3 mmol) were placed in a reaction flask under argon protection.
2. Anhydrous THF (60 ml) was added to dissolve 5-hydroxy-1H-indole-3-acetic acid (5.00 g, 26.2 mmol) and THF (100 ml) was added dropwise over 30 min.
3. The reaction mixture was heated to reflux for 3 hours.
4. After completion of the reaction, the reaction was cooled in an ice bath and THF (10 ml) and H2O (4 ml) were added slowly and stirred for 30 min.
5. The reaction mixture was filtered through diatomaceous earth and the filter cake was washed with dichloromethane (150 ml).
6. The filtrate was concentrated under reduced pressure to give the crude product.
7. Yield: 2.17 g (47%). 8.
8. Product characterization: 1H-NMR (DMSO-d6): δ 2.74 (2H, m); 3.60 (3H, m); 6.58 (1H, m); 6.78 (1H, s); 6.99 (1H, s); 7.08 (1H, d); 10.5 (1H, bs).
in vitro
in previous studies, 5-hydroxy tryptophol was identified as a metabolite of tryptophan that was formed by the alcohol dehydrogenase-catalyzed reduction of the serotonin intermediate, 5-hydroxyindoleacetaldehyde. moreover, depending on the tissue nad/nadh ratio, the acetaldehyde intermediate could also be oxidized by aldehyde dehydrogenase to form 5-hydroxyindoleacetic acid. therefore, the ratio of 5-hydroxy tryptophol to 5-hydroxyindoleacetic acid could be used as a biomarker for recent alcohol consumption [1,2].
References
[1] yokoyama, m. t. and carlson, j.r. dissimilation of tryptophan and related indolic compounds by ruminal microorganisms in vitro. appl.microbiol. 27(3), 540-548 (1974).
[2] beck, o. ,stephanson, n.,btthcer, m., et al. biomarkers to disclose recent intake of alcohol: potential of 5-hydroxytryptophol glucuronide testing using new direct uplc-tandem ms and elisa methods. alcohol & alcoholism 42(4), 321-325 (2007).
