4-Hydroxy atorvastatin hemicalcium is a metabolite of Atorvastatin. Atorvastatin is an orally active HMG-CoA reductase inhibitor with the ability to effectively lower blood lipids. Atorvastatin is metabolized by the cytochrome P450 (CYP) isomer CYP3A4 to form 4-Hydroxy atorvastatin.

Physicochemical Properties

Molecular Formula	C33H35FN2O6.1/2CA
Molecular Weight	594.68
CAS #	265989-44-4
Related CAS #	4-Hydroxy Atorvastatin-d5 calcium;265989-45-5
Appearance	White to off-white solid powder
LogP	6.53
SMILES	FC1C=CC(=CC=1)C1=C(C2C=CC=CC=2)C(C(NC2C=CC(=CC=2)O)=O)=C(C(C)C)N1CCC(CC(CC(=O)O)O)O
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

References

[1]. Long term efficacy and safety of atorvastatin in the treatment of severe type III and combined dyslipidaemia. Heart. 2002;88(3):234-238. [2]. Diabetes Atorvastin Lipid Intervention (DALI) Study Group. The effect of aggressive versus standard lipid lowering by atorvastatin on diabetic dyslipidemia: the DALI study: a double-blind, randomized, placebo-controlled trial in patients with type 2 diabetes and diabetic dyslipidemia. Diabetes Care. 2001;24(8):1335-1341.

Solubility Data

Solubility (In Vitro)

DMSO : ~100 mg/mL (~168.16 mM; with ultrasonication)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (4.20 mM)(saturation unknown) in 10% DMSO 40% PEG300 5% Tween-80 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 and add it to 400 μL PEG300, mix well; then add 50 μL Tween-80 to the above system, mix well; then continue to add 450 μL of normal saline to make up to 1 mL. Preparation of normal saline: Dissolve 0.9 g of sodium chloride in ddH₂O and make up to 100 mL to obtain a clear and transparent normal saline solution. Solubility in Formulation 2: ≥ 2.5 mg/mL (4.20 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 and add it to 900 μL of 20% SBE-β-CD saline solution and mix well. 2 g SBE-β-CD (sulfobutyl ether β-cyclodextrin) powder is diluted to 10 mL of saline and completely dissolved until clear and transparent. Solubility in Formulation 3: ≥ 2.5 mg/mL (4.20 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 and add it to 900 μL corn oil and mix well.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	1.6816 mL	8.4079 mL	16.8158 mL
	5 mM	0.3363 mL	1.6816 mL	3.3632 mL
	10 mM	0.1682 mL	0.8408 mL	1.6816 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.