Skepinone-L (CBS-3830; CBS3830) is a novel, potent, selective, and ATP-competitive p38-MAPK inhibitor that may have anti-inflammatory effects. With an IC50 of 5 nM, it inhibits p38α-MAPK.

Physicochemical Properties

Molecular Formula	C24H21F2NO4
Molecular Weight	425.42
Exact Mass	425.143
Elemental Analysis	C, 67.76; H, 4.98; F, 8.93; N, 3.29; O, 15.04
CAS #	1221485-83-1
Related CAS #	1221485-83-1
PubChem CID	45279963
Appearance	Light yellow to yellow solid powder
Density	1.4±0.1 g/cm3
Boiling Point	629.0±55.0 °C at 760 mmHg
Flash Point	334.2±31.5 °C
Vapour Pressure	0.0±1.9 mmHg at 25°C
Index of Refraction	1.646
LogP	4.95
Hydrogen Bond Donor Count	3
Hydrogen Bond Acceptor Count	7
Rotatable Bond Count	6
Heavy Atom Count	31
Complexity	608
Defined Atom Stereocenter Count	1
SMILES	O=C1C2=CC(OC[C@@H](CO)O)=CC=C2CCC3=C1C=CC(NC4=CC=C(C=C4F)F)=C3
InChi Key	HXMGCTFLLWPVFM-GOSISDBHSA-N
InChi Code	InChI=1S/C24H21F2NO4/c25-16-4-8-23(22(26)10-16)27-17-5-7-20-15(9-17)2-1-14-3-6-19(11-21(14)24(20)30)31-13-18(29)12-28/h3-11,18,27-29H,1-2,12-13H2/t18-/m1/s1
Chemical Name	13-(2,4-difluoroanilino)-5-[(2R)-2,3-dihydroxypropoxy]tricyclo[9.4.0.03,8]pentadeca-1(11),3(8),4,6,12,14-hexaen-2-one
Synonyms	CBS3830; CBS-3830; CBS 3830; Skepinone-L
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

Targets	p38α (IC50 = 5 nM)
ln Vitro	Skepinone-L reduces TNF-α, IL-1β, and IL-10 concentrations, which are controlled by p38 MAPK, with an IC50 range of 30 to 50 nM and exhibits concentration-dependent inhibition of HSP27 (Ser82) phosphorylation through the p38 MAPK pathway.[1] Skepinone-L (1 μM) reduces platelet secretion and aggregation by inhibiting the phosphorylation of the platelet p38 MAPK substrate Hsp27 that is activated by stimulation with CRP, thrombin, or the thromboxane A2 analogue U-46619. [2]
ln Vivo	Skepinone-L inhibits TNF-induced release from Gal/LPS by 77% in living organisms. [1]
Enzyme Assay	Skepinone-L (CBS3830), the first ATP-competitive p38 MAPK inhibitor with excellent in vivo efficacy and selectivity. Therefore, Skepinone-L (CBS3830) is a valuable probe for chem. biol. research, and it may foster the development of a unique class of kinase inhibitors.
Animal Protocol	Mice ~3 mg/kg Oral administration
References	[1]. Nat Chem Biol . 2011 Dec 25;8(2):141-3. [2]. Cell Physiol Biochem . 2013;31(6):914-24.

Solubility Data

Solubility (In Vitro)

DMSO: ~85 mg/mL (~199.8 mM) Water: <1 mg/mL Ethanol: ~85 mg/mL (~199.8 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.88 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.5 mg/mL (5.88 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly. Solubility in Formulation 3: 0.5% methylcellulose: 30mg/mL  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.3506 mL	11.7531 mL	23.5062 mL
	5 mM	0.4701 mL	2.3506 mL	4.7012 mL
	10 mM	0.2351 mL	1.1753 mL	2.3506 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.