DL-Buthionine-(S,R)-sulfoximine HCl (Buthionine sulfoximine HCl) is a potent inhibitor of glutamylcysteine synthetase biosynthesis.

Physicochemical Properties

Molecular Formula	C8H19CLN2O3S
Molecular Weight	258.77
Related CAS #	DL-Buthionine-(S,R)-sulfoximine;5072-26-4;L-Buthionine-(S,R)-sulfoximine hydrochloride
Appearance	Typically exists as solid at room temperature
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 (e.g. under nitrogen), avoid exposure to moisture and light.
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	Glutamylcysteine synthetase[1]
ln Vitro	Buthionine sulfoximine is a methionine sulfoximine analog that inhibits gamma-glutamylcysteine synthetase more than prothionine sulfoximine by at least 100 times and more than 20 times, respectively[1].
ln Vivo	Continuous intravenous infusion of nontoxic doses of D,L-Buthionine-(S,R)-sulfoximine (300 and 600 mg/kg/day) in mice harboring HT1080 and HT1080/DR4 xenografts results in a 60% decrease in GSH plasma levels and a greater than 95% reduction in GSH tumor levels in both parental and multidrug-resistant tumors[2].
References	[1]. Potent and specific inhibition of glutathione synthesis by buthionine sulfoximine (S-n-butyl homocysteine sulfoximine). J Biol Chem. 1979 Aug 25;254(16):7558-60. [2]. d,l-buthionine-(S,R)-sulfoximine potentiates in vivo the therapeutic efficacy of doxorubicin against multidrug resistance protein-expressing tumors. Clin Cancer Res. 1996 Dec;2(12):1961-8.

Solubility Data

Solubility (In Vitro)	H2O :~100 mg/mL (~386.44 mM) DMSO :< 1 mg/mL
Solubility (In Vivo)	Solubility in Formulation 1: 100 mg/mL (386.44 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	3.8644 mL	19.3222 mL	38.6444 mL
	5 mM	0.7729 mL	3.8644 mL	7.7289 mL
	10 mM	0.3864 mL	1.9322 mL	3.8644 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.