4-Ethynyl-L-phenylalanine hydrochloride

p-Ethynylphenylalanine hydrochloride (4-Ethynyl-L-phenylalanine hydrochloride) is a potent, selective, reversible and competitive inhibitor of tryptophan hydroxylase (TPH), with a Ki of 32.6 μM[1]. p-Ethynylphenylalanine (hydrochloride) is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.

[1] Stokes AH, et al. p-ethynylphenylalanine: a potent inhibitor of tryptophan hydroxylase. J Neurochem. 2000 May;74(5):2067-73. DOI:10.1046/j.1471-4159.2000.0742067.x