N-Acetyl lysyltyrosylcysteine amide is a potent, reversible, specific and nontoxic tripeptide inhibitor of myeloperoxidase (MPO). N-Acetyl lysyltyrosylcysteine amide can effectively inhibit the production of toxic oxidants by MPO in vivo. N-Acetyl lysyltyrosylcysteine amide reduces neuronal damage in the brain after stroke and preserves brain tissue and neurological function. N-Acetyl lysyltyrosylcysteine amide inhibits MPO-dependent hypochlorous acid (HOCl) production, protein nitration and LDL oxidation.

Physicochemical Properties

Molecular Formula	C20H31N5O5S
Molecular Weight	453.555643320084
Exact Mass	453.204
CAS #	1287585-40-3
PubChem CID	51352312
Appearance	White to off-white solid powder
LogP	-0.9
Hydrogen Bond Donor Count	7
Hydrogen Bond Acceptor Count	7
Rotatable Bond Count	13
Heavy Atom Count	31
Complexity	613
Defined Atom Stereocenter Count	3
SMILES	SCC(C(N)=O)NC(C(CC1C=CC(=CC=1)O)NC(C(CCCCN)NC(C)=O)=O)=O
InChi Key	JTHKLTJLEVKKFW-ULQDDVLXSA-N
InChi Code	InChI=1S/C20H31N5O5S/c1-12(26)23-15(4-2-3-9-21)19(29)24-16(10-13-5-7-14(27)8-6-13)20(30)25-17(11-31)18(22)28/h5-8,15-17,27,31H,2-4,9-11,21H2,1H3,(H2,22,28)(H,23,26)(H,24,29)(H,25,30)/t15-,16-,17-/m0/s1
Chemical Name	(2S)-2-acetamido-6-amino-N-[(2S)-1-[[(2R)-1-amino-1-oxo-3-sulfanylpropan-2-yl]amino]-3-(4-hydroxyphenyl)-1-oxopropan-2-yl]hexanamide
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: This product requires protection from light (avoid light exposure) during transportation and storage.
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

ln Vivo	In the brains of middle cerebral artery occlusion (MCAO) mice, N-acetyl lysyltyrosylcysteine amide (KYC) dramatically reduces infarct size, blood-brain barrier leakage, myeloid cell infiltration, neuronal loss, and apoptosis[1]. In MCAO mice, N-acetyl lysyltyrosylcysteine amide (10 mg/kg; ip; daily for 3–7 days) dramatically lowers infarct size and neurological severity scores[1]. N-Acetyl lysyltyrosylcysteine amide (10 mg/kg; intraperitoneally; daily for 7 days) dramatically reduces neutrophil infiltration and preserves BBB function. In MCAO mice, N-acetyl lysyltyrosylcysteine amide (10 mg/kg; ip; daily 7 days) dramatically decreases neuron loss and microglia/macrophage activation. In the brains of MCAO mice, N-acetyl lysyltyrosylcysteine amide (10 mg/kg; ip; daily for 3–7 days) reduces cell damage and apoptosis. In MCAO mice's brains, N-acetyl lysyltyrosylcysteine amide decreased MPO.
Animal Protocol	Animal/Disease Models: 8-10 weeks old C57BL/6J mice (middle cerebral artery occlusion (MCAO) mode)[1] Doses: 10 mg/kg Route of Administration: Ip; daily for 3-7 days Experimental Results: Dramatically decreased neurological deficit and brain infarct size in mice subjected to MCAO.
References	[1]. Inhibition of myeloperoxidase oxidant production by N-acetyl lysyltyrosylcysteine amide reduces brain damage in a murine model of stroke [published correction appears in J Neuroinflammation. 2016;13(1):166]. J Neuroinflammation. 2016;13(1):11. [2]. N-acetyl lysyltyrosylcysteine amide inhibits myeloperoxidase, a novel tripeptide inhibitor. J Lipid Res. 2013;54(11):3016-3029.

Solubility Data

Solubility (In Vivo)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.2048 mL	11.0239 mL	22.0478 mL
	5 mM	0.4410 mL	2.2048 mL	4.4096 mL
	10 mM	0.2205 mL	1.1024 mL	2.2048 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.