SK1-I HCl (BML-258 HCl) is an analog of sphingosine and an isozyme-specific competitive inhibitor of SPHK1 with a Ki of 10 µM. SK1-I HCl has no activity against SPHK2, PKCα, PKCδ, PKA, AKT1, ERK1, EGFR, CDK2, IKKβ or CamK2β. SK1-I HCl enhances autophagy and has anticancer effect.

Physicochemical Properties

Molecular Formula	C17H27NO2.CLH
Molecular Weight	313.87
Exact Mass	313.18
CAS #	2366222-05-9
Related CAS #	SK1-I;1072443-89-0
PubChem CID	49793059
Appearance	Colorless to light yellow liquid
Hydrogen Bond Donor Count	4
Hydrogen Bond Acceptor Count	3
Rotatable Bond Count	9
Heavy Atom Count	21
Complexity	260
Defined Atom Stereocenter Count	2
SMILES	CCCCCC1=CC=C(C=C1)/C=C/[C@@H]([C@@H](CO)NC)O.Cl
InChi Key	SGCJOKUPGVFNKS-UUCPMUBFSA-N
InChi Code	InChI=1S/C17H27NO2.ClH/c1-3-4-5-6-14-7-9-15(10-8-14)11-12-17(20)16(13-19)18-2;/h7-12,16-20H,3-6,13H2,1-2H3;1H/b12-11+;/t16-,17+;/m1./s1
Chemical Name	(E,2R,3S)-2-(methylamino)-5-(4-pentylphenyl)pent-4-ene-1,3-diol;hydrochloride
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: Please store this product in a sealed and protected environment, avoid exposure to moisture.
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	SphK1
ln Vitro	In HCT116 cells and HCT116 cells expressing TP53 null tumors, SK1-I hydrochloride (0-10 μM; 24 hours) attenuates cancer cell proliferation and survival in a TP53-dependent manner[2]. Compared to HCT116 cells without TP53, SK1-I hydrochloride (0–20 μM; 12 hours) causes more CASP3 cleavage in HCT116 cells, resulting in a characteristic of apoptosis[2].
ln Vivo	The hypotensive response is greatly reduced when SK1-I hydrochloride (BML-258 hydrochloride; intraperitoneal (ip) injection; once; 24 hours previous to baseline mean arterial blood pressure (MAP); 75 mg/kg) is administered before anandamide (iv injection; two doses; 1 and 10 mg/kg)[3].
Cell Assay	Cell Viability Assay[2] Cell Types: HCT116 cells and HCT116 cells bearing TP53 null cancer Tested Concentrations: 0 µM, 2.5 µM, 5 µM, 7.5 µM, 10 µM Incubation Duration: 24 hrs (hours) Experimental Results: diminished cancer cell growth and survival. Western Blot Analysis[2] Cell Types: HCT116 cells and HCT116 cells bearing TP53 null cancer Tested Concentrations: 0 µM, 5 µM , 10 µM, 20 µM Incubation Duration: 12 hrs (hours) Experimental Results: Induced more CASP3 cleavage in HCT116 cells, compared to HCT116 cells lacking TP53.
Animal Protocol	Animal/Disease Models: Male C57BL/6 mice (24 ± 3.5 g)[3] Doses: 75 mg/kg Route of Administration: intraperitoneal (ip) injection; once; 24 hrs (hours) prior to baseline MAP measurement Experimental Results: Dramatically lowered baseline mean arterial blood pressure (MAP).
References	[1]. Inhibitors of the sphingosine kinase pathway as potential therapeutics. Curr Cancer Drug Targets. 2010 Jun;10(4):354-67. [2]. TP53 is required for BECN1- and ATG5-dependent cell death induced by sphingosine kinase 1 inhibition. Autophagy. 2018;14(6):942-957. [3]. Requirement for sphingosine kinase 1 in mediating phase 1 of the hypotensive response to anandamide in the anaesthetised mouse. Eur J Pharmacol. 2019 Jan 5;842:1-9.

Solubility Data

Solubility (In Vitro)

DMSO: 250 mg/mL (796.53 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (6.63 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 20.8 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: ≥ 2.08 mg/mL (6.63 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in 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 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. 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. Solubility in Formulation 3: ≥ 2.08 mg/mL (6.63 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 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	3.1860 mL	15.9302 mL	31.8603 mL
	5 mM	0.6372 mL	3.1860 mL	6.3721 mL
	10 mM	0.3186 mL	1.5930 mL	3.1860 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.