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LX-1031TPH inhibitor


Catalog No. A3565
Size Price Stock Qty
10mM (in 1mL DMSO) $155.00 In stock
5mg $123.00 In stock
25mg $287.00 In stock
100mg $617.00 In stock
250mg $1,131.00 In stock

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Sample solution is provided at 25 µL, 10mM.

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Chemical structure


Biological Activity

Description LX-1031 is an oral, small molecule inhibitor of tryptophan 5-hydroxylase (TPH).
Targets TPH          

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Chemical Properties

Cas No. 945976-76-1 SDF Download SDF
Synonyms LX1031; LX 1031
Chemical Name (2S)-2-amino-3-[4-[2-amino-6-[(1R)-2,2,2-trifluoro-1-[4-(3-methoxyphenyl)phenyl]ethoxy]pyrimidin-4-yl]phenyl]propanoic acid
Canonical SMILES COC1=CC=CC(=C1)C2=CC=C(C=C2)C(C(F)(F)F)OC3=NC(=NC(=C3)C4=CC=C(C=C4)CC(C(=O)O)N)N
Formula C28H25F3N4O4 M.Wt 538.52
Solubility Soluble in DMSO Storage Store at -20°C
General tips For obtaining a higher solubility , please warm the tube at 37 ℃ and shake it in the ultrasonic bath for a while.Stock solution can be stored below -20℃ for several months.
Shipping Condition Evaluation sample solution : ship with blue ice
All other available size: ship with RT , or blue ice upon request


Tryptophan hydroxylase (TPH) is a key enzyme in the synthesis of serotonin. Serotonin plays important physiological roles both peripherally and centrally. LX-1031 is a heterocyclic substituted phenylalanine analog, an oral small molecule tryptophan hydroxylase (TPH) inhibitor that reduces synthesis of serotonin (5-HT) peripherally and is being developed for conditions characterized by excess 5-HT expression such as diarrhea-predominant irritable bowel syndrome (IBS-D) and, possibly, carcinoid diarrhea.

In vitro: LX-1031 inhibits TPH1 at its concentration of 10-8–10-7 mol L-1 range [1].

In vivo: With oral administration of LX-1031 in mice, the 5-HT reductions in the jejunum relative to control were ~33%, 51%, and 66% with the 15, 45 and 135 mg/kg/day doses, respectively; the effect of 5 mg/kg/day on GI 5-HT content was not significantly different from control [2].

Clinical trial: In double-blind studies (doses of LX-1031 ranging from 250 to 1000 mg q.i.d.), average 5HIAA reductions of 33% were noted. In phase I studies, 54 healthy volunteers received the drug for up to 14 days while the diet was strictly controlled to avoid 5-HT-rich foods. Twenty four hour urine collections were obtained. Significant reductions in urinary 5-HIAA persisted over the duration of exposure [3].

[1] Camilleri M.  LX-1031, a tryptophan 5-hydroxylase inhibitor, and its potential in chronic diarrhea associated with increased serotonin. Neurogastroenterol Motil. 2011;23(3):193-200.
[2] Brown PM, Jackson JI, Frazier KS, Turner CA, Shi ZC, Liu Q.  From mouse knockout to investigational drug: LX1031, a novel potential treatment for irritable bowel syndrome. Am J Gastroenterol 2007; 102: S961 (Abstract).
[3] Freiman J, Jackson J, Frazier KS, Yang QM, Liu Q, Brown P.   LX1031: inhibition of 5-HT synthesis as a new target in the management of irritable bowel syndrome (IBS). Neurogastroenterol Motil 2009; 21: 250.