| Field | Specification |
|---|---|
| Target | |
| Alternative names | 5-Iodo-2′-deoxyuridine; 5-IUdR; IdUrd |
| CAS no. | |
| Applications | |
| Molecular weight | |
| Molecular formula | C9H11IN2O5 |
| Purity | |
| SMILES | |
| Form | Solid |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
Idoxuridine, also known as 5-Iodo-2′-deoxyuridine, 5-IUdR, and IdUrd, is an iodinated thymidine analogue that competitively inhibits phosphorylases. It can inhibit viral activity, particularly viral eye infections such as herpes simplex keratitis, by inhibiting DNA polymerase and affecting viral replication. Against feline herpesvirus, it has an IC50 value of 4.3 μM[1], and it also shows anti-orthopoxvirus activity. It is supplied as a white to off-white solid (C9H11IN2O5, MW 354.10) at 99.81% purity.
Physical & Chemical Properties
| CAS Number | 54-42-2 |
|---|---|
| Molecular Formula | C9H11IN2O5 |
| Molecular Weight | 354.10 g/mol |
| Purity | 99.81% |
| Appearance | Solid |
| Color | White to off-white |
| SMILES | O=C(N1)N([C@H]2C[C@H](O)[C@@H](CO)O2)C=C(I)C1=O |
| Target | HSV-1, DNA Polymerase |
| Signaling Pathway | Cell Cycle/DNA Damage; Metabolic Enzyme/Protease; Anti-infection |
| Solubility | In Vitro: DMSO: 100 mg/mL (282.41 mM; Requires sonication and warming and heat to 60°C; Hygroscopic DMSO has a significant impact on the solubility of product, please use newly opened DMSO) H2O: 2.5 mg/mL (7.06 mM; Requires sonication and warming and heat to 60°C) |
| Storage | Powder: -20°C, 3 years; 4°C, 2 years. In solvent: -80°C, 6 months; -20°C, 1 month. |
| Shipping | Room temperature in continental US; may vary elsewhere. |
Literature Cited
Sources cited in this description and in the In Vitro & In Vivo Data tab. Peer-reviewed publications that used this product are listed under References.
Safety
For Research Use Only. Not for use in diagnostic or therapeutic procedures, and not for human or veterinary use. Handle in accordance with the Safety Data Sheet and your institution's chemical hygiene plan.
In Vitro
| Solvent | Solubility | Notes |
|---|---|---|
| DMSO | 100 mg/mL (282.41 mM) | requires sonication and warming and heat to 60°C; use freshly opened DMSO (absorbed moisture lowers solubility) |
| H2O | 2.5 mg/mL (7.06 mM) | requires sonication and warming and heat to 60°C |
Aliquot the stock solution and store it at -80°C (up to 6 months) or -20°C (up to 1 month); avoid repeated freeze-thaw cycles.
If water is used as the stock solvent, dilute to the working solution and sterilize it through a 0.22 μm filter before use.
In Vivo
Choose the formulation that suits the animal model and route of administration; percentages are volume ratios of the final working solution. Start from a clear DMSO stock (see In Vitro above), add the co-solvents one at a time in the order listed, mixing after each addition, and prepare the working solution fresh on the day of dosing. If precipitation or phase separation occurs, gentle warming or sonication can help.
Protocol 1
| Composition | 10% DMSO + 40% PEG300 + 5% Tween-80 + 45% saline |
|---|---|
| Result | ≥ 2.08 mg/mL (5.87 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.08 mg/mL (saturation not determined). For 1 mL of working solution: add 100 μL DMSO stock (20.8 mg/mL) to 400 μL PEG300; then 50 μL Tween-80; then 450 μL saline to bring the volume to 1 mL. Saline: dissolve 0.9 g sodium chloride in ddH2O and make up to 100 mL. |
Protocol 2
| Composition | 10% DMSO + 90% (20% SBE-β-CD in saline) |
|---|---|
| Result | ≥ 2.08 mg/mL (5.87 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.08 mg/mL (saturation not determined). For 1 mL of working solution: add 100 μL DMSO stock (20.8 mg/mL) to 900 μL 20% SBE-β-CD in saline. 20% SBE-β-CD in saline: dissolve 2 g SBE-β-CD powder in 10 mL saline until clear (4°C, store up to one week). |
Protocol 3
| Composition | 10% DMSO + 90% Corn Oil |
|---|---|
| Result | ≥ 2.08 mg/mL (5.87 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.08 mg/mL (saturation not determined). Use with caution if continuous dosing will exceed two weeks. For 1 mL of working solution: add 100 μL DMSO stock (20.8 mg/mL) to 900 μL corn oil. |
Data provided by the manufacturer.
In Vitro
Idoxuridine (2-10 μM, 72 hours) shows antiviral activity with an IC50 value of 4.3 μM[1].
Cell Proliferation Assay[1]
| Cell Line | Crandell-Reese feline kidney (CRFK) cells |
|---|---|
| Concentration | 2-10 μM |
| Incubation Time | 72 hours |
| Result | Showed the IC50 value of 4.3 μM. |
Cell Cytotoxicity Assay[1]
| Cell Line | Crandell-Reese feline kidney (CRFK) cells |
|---|---|
| Concentration | 5-50 μM |
| Incubation Time | 72 hours |
| Result | Reduced by 10.8% relatively in CRFK cells. |
In Vivo
In C3HeB/FeJ female and male mice and A/J male mice, Idoxuridine (intraperitoneal injection, 50-200 mg/kg, 3 times, 3 hours apart) can increase the production of hemolysin plaque-forming cells (HPFC) against sheep red blood cells (SRBC)[2].
| Animal Model | C3HeB/FeJ female and male mice and A/J male mice, aged 2 to 4 months[2] |
|---|---|
| Dosage | 50-200 mg/kg |
| Administration | Intraperitoneal injection, 3 times, 3 hours interval |
| Result | Stimulated the production of hemolysin plaque-forming cells (HPFC) to sheep red blood cells (SRBC) in the dose range of 50-200 mg/kg. |
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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