KP136 (AL136) is a potent, orally bioactive antiallergic agent. Inhibits histamine release and cell degranulation with IC50 of 76.1 μg/mL and 63 μg/mL respectively.

Physicochemical Properties

Molecular Formula	C16H18N4O3
Molecular Weight	314.345
Exact Mass	314.138
CAS #	76239-32-2
PubChem CID	166484
Appearance	Typically exists as solid at room temperature
Density	1.289g/cm3
Boiling Point	556.9ºC at 760 mmHg
Flash Point	290.6ºC
Index of Refraction	1.594
LogP	2.932
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	7
Heavy Atom Count	23
Complexity	443
Defined Atom Stereocenter Count	0
SMILES	O=C1C(C2=NNN=N2)=CC3=CC=CC(OCCCCCC)=C3O1
InChi Key	GUIWTWATPUPDDY-UHFFFAOYSA-N
InChi Code	InChI=1S/C16H18N4O3/c1-2-3-4-5-9-22-13-8-6-7-11-10-12(15-17-19-20-18-15)16(21)23-14(11)13/h6-8,10H,2-5,9H2,1H3,(H,17,18,19,20)
Chemical Name	8-hexoxy-3-(2H-tetrazol-5-yl)chromen-2-one
Synonyms	KP-136; KP136; KP 136
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
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 Vitro	KP136 (0.01 μg/mL) demonstrated a dose-dependent inhibition of histamine release and degranulation, indicating its status as an inhibitor of mast cell activation. 76.1 μg/mL is the IC50 for histamine release, whereas 63 ug/mL is the IC50 for degranulation[1].
ln Vivo	In comparison to 1 mg/kg KP136 (KP-136) or 5 mg/kg DSCG, 0.2 mg/kg of C4C has an equipotent impact. Although KP136 exhibits an overt inhibitory effect of roughly 66% at the oral dose of 2 mg/kg, C4C is less effective when taken orally because it only provides a maximum inhibition of about 35% even at the high dose of 100 mg/kg. But KP136 (1 mg/kg, i.v.) also exhibits remarkable inhibition of 5-hour homologous PCA, with an activity akin to that of C4C[1].
References	[1]. Antiallergic effects of 4-[2-oxo-3-(1H-tetrazol-5-yl)-2H-chromen-8-yloxy]-bu tyric acid. Jpn J Pharmacol. 1989 Jun;50(2):111-8.

Solubility Data

Solubility (In Vitro)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

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	3.1812 mL	15.9058 mL	31.8117 mL
	5 mM	0.6362 mL	3.1812 mL	6.3623 mL
	10 mM	0.3181 mL	1.5906 mL	3.1812 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.