NS-398 is a nonsteroidal anti~inflammatory agent with antipyretic properties that has been studied for pain relief. NS-398 can selectively inhibit the activity of COX-2 with IC50 of 3.8 μM. It has no effect on the activity of COX-1 at a concentration of 100 μM.

Physicochemical Properties

Molecular Formula	C13H18N2O5S
Molecular Weight	314.36
Exact Mass	314.093
CAS #	123653-11-2
PubChem CID	4553
Appearance	Light yellow to yellow solid powder
Density	1.4±0.1 g/cm3
Boiling Point	490.6±55.0 °C at 760 mmHg
Melting Point	139 °C
Flash Point	250.5±31.5 °C
Vapour Pressure	0.0±1.2 mmHg at 25°C
Index of Refraction	1.593
LogP	3.67
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	4
Heavy Atom Count	21
Complexity	450
Defined Atom Stereocenter Count	0
SMILES	0
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	Non-steroidal anti-inflammatory drug NS-398 acts as an antagonist of G/H synthase/cyclooxygenase (COX-2) and has no effect on COX-1 at 100 μM. Its IC50 is 3.8 μM. [1]. Sheep seminal vesicle microsomes exhibit a weak inhibition of PG endoperoxide synthase activity by NS-398 (IC50: 11 μM)[2].
ln Vivo	NS-398 (0.5–10 mg/kg, po) had an antipyretic and rotational sedative effect (ED50, 1.84 mg/kg), as well as an efficacious venous return amyloid (ED30, 1.14 mg/kg) and effective management of auxiliary arthritis (ED 30, 4.69 mg/kg). With an ED50 of 8.2 mg/kg, NS-398 GFP induced a writhing reaction in mice [2].
References	[1]. NS-398, a new anti-inflammatory agent, selectively inhibits prostaglandin G/H synthase/cyclooxygenase (COX-2) activity in vitro. Prostaglandins. 1994 Jan;47(1):55-9. [2]. NS-398, a novel non-steroidal anti-inflammatory drug with potent analgesic and antipyretic effects, which causes minimal stomach lesions. Gen Pharmacol. 1993 Jan;24(1):105-10.
Additional Infomation	NS-398 is a C-nitro compound that is N-methylsulfonyl-4-nitroaniline bearing an additional cyclohexyloxy substituent at position 2. It has a role as a cyclooxygenase 2 inhibitor and an antineoplastic agent. It is a sulfonamide, an aromatic ether and a C-nitro compound. It is functionally related to a 4-nitroaniline. NS-398 is a COX-2 inhibitor. It was developed as part of the mechanistic study of the cyclooxygenases. N-(2-Cyclohexyloxy-4-nitrophenyl)methanesulfonamide has been reported in Plantago major with data available.

Solubility Data

Solubility (In Vitro)

DMSO : ~33.33 mg/mL (~106.02 mM)

Solubility (In Vivo)

Solubility in Formulation 1: 2.5 mg/mL (7.95 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with sonication. 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 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 2: ≥ 1.67 mg/mL (5.31 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 16.7 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 3: ≥ 1.67 mg/mL (5.31 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 16.7 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	3.1811 mL	15.9053 mL	31.8107 mL
	5 mM	0.6362 mL	3.1811 mL	6.3621 mL
	10 mM	0.3181 mL	1.5905 mL	3.1811 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.