Pricing Availability   Qty
Description: Potent and selective NK1 antagonist
Chemical Name: N-Acetyl-L-tryptophan 3,5-bis(trifluoromethyl)benzyl ester
Purity: ≥98% (HPLC)
Citations (2)
Literature (2)

Biological Activity for L-732,138

L-732,138 is a potent and highly selective competitive tachykinin NK1 receptor antagonist (IC50 = 2.3 nM).

Licensing Information

Sold with the permission of Merck Sharp and Dohme Ltd.

Technical Data for L-732,138

M. Wt 472.39
Formula C22H18F6N2O3
Storage Store at RT
Purity ≥98% (HPLC)
CAS Number 148451-96-1
PubChem ID 44396853
Smiles O=C(N[C@@](CC2=CNC3=C2C=CC=C3)([H])C(OCC1=CC(C(F)(F)F)=CC(C(F)(F)F)=C1)=O)C

The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis.

Tocris products are intended for laboratory research use only, unless stated otherwise.

Solubility Data for L-732,138

Solvent Max Conc. mg/mL Max Conc. mM
ethanol 47.24 100
DMSO 47.24 100

Preparing Stock Solutions for L-732,138

The following data is based on the product molecular weight 472.39. Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Select a batch to recalculate based on the batch molecular weight:
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 2.12 mL 10.58 mL 21.17 mL
5 mM 0.42 mL 2.12 mL 4.23 mL
10 mM 0.21 mL 1.06 mL 2.12 mL
50 mM 0.04 mL 0.21 mL 0.42 mL

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Product Datasheets for L-732,138

Certificate of Analysis / Product Datasheet
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References for L-732,138

References are publications that support the biological activity of the product.

Cascieri et al (1994) Characterization of the interaction of N-acyl-L-tryptophan benzyl ester neurokinin antagonists with the human neurokinin-1 receptor. J.Biol.Chem. 269 6587 PMID: 7509807

Kuo et al (1998) Lipopolysaccharide enhances neurogenic plasma exudation in guinea-pig airways. Br.J.Pharmacol. 125 711 PMID: 9831906

MacLeod et al (1993) N-Acyl-L-tryptophan benzyl esters: potent substance P receptor antagonists. J.Med.Chem. 36 2044 PMID: 8393115

MacLeod et al (1994) Identification of L-tryptophan derivatives with potent and selective antagonist activity at the NK1 receptor. J.Med.Chem. 37 1269 PMID: 7513763

If you know of a relevant reference for L-732,138, please let us know.

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Keywords: L-732,138, L-732,138 supplier, Potent, selective, NK1, antagonists, Tachykinin, Receptors, Neurokinin, L732138, merck, Receptor, 0868, Tocris Bioscience

2 Citations for L-732,138

Citations are publications that use Tocris products. Selected citations for L-732,138 include:

Wan et al (2017) Endomorphin-2 Inhibition of Substance P Signaling within Lamina I of the Spinal Cord Is Impaired in Diabetic Neuropathic Pain Rats. Front Mol Neurosci 9 167 PMID: 28119567

Li et al (2013) Neurotransmitter substance P mediates pancreatic cancer perineural invasion via NK-1R in cancer cells. J Neurosci 11 294 PMID: 23345604

Do you know of a great paper that uses L-732,138 from Tocris? Please let us know.

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Literature in this Area

Tocris offers the following scientific literature in this area to showcase our products. We invite you to request* your copy today!

*Please note that Tocris will only send literature to established scientific business / institute addresses.

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Major depressive disorder is characterized by depressed mood and a loss of interest and/or pleasure. Updated in 2015 this poster highlights presynaptic and postsynaptic targets for the potential treatment of major depressive disorder, as well as outlining the pharmacology of currently approved antidepressant drugs.