NS-2028 is a selective soluble guanylate cyclase (sGC) inhibitor (antagonist) with IC50s of 30 nM and 200 nM for basal and NO-stimulated enzyme activities, respectively. NS-2028 inhibits soluble guanylyl cyclase activity in mouse cerebellar homogenate and neuronal NO synthase, with IC50s of 17 nM and 20 nM, respectively. NS-2028 inhibits the formation of cyclic GMP by 3-morpholino-sydnonimine (SIN-1) in human cultured umbilical vein endothelial cells with IC50 of 30 nM. NS-2028, commonly utilized in study/research of nitric oxide signaling pathways, completely inhibits NO-dependent relaxation responses in non-vascular smooth muscle (1μM). NS-2028 reduces vascular endothelial growth factor-induced angiogenesis and permeability.

Physicochemical Properties

Molecular Formula	C9H5BRN2O3
Molecular Weight	269.05
Exact Mass	267.948
CAS #	204326-43-2
PubChem CID	4551
Appearance	White to off-white solid powder
Density	2.1±0.1 g/cm3
Boiling Point	353.8±52.0 °C at 760 mmHg
Melting Point	161-162ºC
Flash Point	167.8±30.7 °C
Vapour Pressure	0.0±0.8 mmHg at 25°C
Index of Refraction	1.778
LogP	0.27
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	0
Heavy Atom Count	15
Complexity	333
Defined Atom Stereocenter Count	0
InChi Key	MUDRLQRJCGJJTB-UHFFFAOYSA-N
InChi Code	InChI=1S/C9H5BrN2O3/c10-5-1-2-7-6(3-5)12-8(4-14-7)11-15-9(12)13/h1-3H,4H2
Chemical Name	8-bromo-4H-[1,2,4]oxadiazolo[3,4-c][1,4]benzoxazin-1-one
Synonyms	NS2028 NS-2028 NS 2028
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	When compared to cells cultured in a vehicle, NS -2028 (10 μM) suppresses cell number growth by 25% [2]. By preventing p38 MAPK activation, NS -2028 (10 μM; 30 min) stimulates cell proliferation test in the presence of VEGF [2].
ln Vivo	After VEGF particles were ingested, NS-2028 (a powder medication; 1 g/L; 8 days) dramatically decreased the formation of new blood vessels in avascular rabbits [2].
Cell Assay	Cell Proliferation Assay[2] Cell Types: HUVEC Cell Tested Concentrations: 10 μM Incubation Duration: 24 hrs (hours) Experimental Results: diminished number of cells in culture. EC migration[2]. Western Blot Analysis[2] Cell Types: HUVEC Cell Tested Concentrations: 10 μM Incubation Duration: 30 minutes Experimental Results: VEGF-enhanced p38 phosphorylation is attenuated.
Animal Protocol	Animal/Disease Models: Rabbit[2] Doses: 1 g/L Route of Administration: Oral administration; 1 g/L; 8 days Experimental Results: Inhibits VEGF-induced angiogenesis in vivo.
References	[1]. Characterization of NS 2028 as a specific inhibitor of soluble guanylyl cyclase. Br J Pharmacol. 1998 Jan;123(2):299-309. [2]. The soluble guanylyl cyclase inhibitor NS-2028 reduces vascular endothelial growth factor-induced angiogenesis and permeability. Am J Physiol Regul Integr Comp Physiol. 2010 Mar;298(3):R824-32.

Solubility Data

Solubility (In Vitro)

DMSO : ~250 mg/mL (~929.20 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.17 mg/mL (8.07 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 21.7 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: ≥ 2.17 mg/mL (8.07 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 21.7 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	3.7168 mL	18.5839 mL	37.1678 mL
	5 mM	0.7434 mL	3.7168 mL	7.4336 mL
	10 mM	0.3717 mL	1.8584 mL	3.7168 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.