S-(2-Carboxypropyl)-L-cysteine (β-Isobuteine) is a urinary metabolite and a metabolic marker of leigh-like syndrome.

Physicochemical Properties

Molecular Formula	C7H13NO4S
Molecular Weight	207.25
Exact Mass	207.057
CAS #	6852-42-2
PubChem CID	151433
Appearance	White to off-white solid powder
LogP	0.552
Hydrogen Bond Donor Count	3
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	6
Heavy Atom Count	13
Complexity	197
Defined Atom Stereocenter Count	1
SMILES	CC(CSC[C@@H](C(=O)O)N)C(=O)O
InChi Key	QSPWUNSFUXUUDG-AKGZTFGVSA-N
InChi Code	InChI=1S/C7H13NO4S/c1-4(6(9)10)2-13-3-5(8)7(11)12/h4-5H,2-3,8H2,1H3,(H,9,10)(H,11,12)/t4?,5-/m0/s1
Chemical Name	3-[(2R)-2-amino-2-carboxyethyl]sulfanyl-2-methylpropanoic acid
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.
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

Solubility Data

Solubility (In Vitro)

DMSO: 25 mg/mL (120.63 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (12.06 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 (12.06 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 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 3: ≥ 2.5 mg/mL (12.06 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.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	4.8251 mL	24.1255 mL	48.2509 mL
	5 mM	0.9650 mL	4.8251 mL	9.6502 mL
	10 mM	0.4825 mL	2.4125 mL	4.8251 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.