| Field | Specification |
|---|---|
| Target | |
| CAS no. | |
| Applications | |
| Molecular weight | |
| Molecular formula | C17H20ClN3O |
| Purity | |
| SMILES | |
| Form | Solid |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
Phentolamine hydrochloride is an orally active, selective antagonist of α1- and α2-adrenergic receptors. It antagonizes the vasodilatory effect of cromakalim on isolated circumflex coronary artery segments in dogs, reduces systemic vascular resistance, and increases cardiac output. It also improves erectile dysfunction and can be used in research on erectile dysfunction[1][2][3]. It is supplied as an off-white to light yellow solid (C17H20ClN3O, MW 317.82) at 99.91% purity.
Physical & Chemical Properties
| CAS Number | 73-05-2 |
|---|---|
| Molecular Formula | C17H20ClN3O |
| Molecular Weight | 317.82 g/mol |
| Purity | 99.91% |
| Appearance | Solid |
| Color | Off-white to light yellow |
| SMILES | OC1=CC=CC(N(CC2=NCCN2)C3=CC=C(C)C=C3)=C1.[H]Cl |
| Target | α1-adrenergic receptor, α2-adrenergic receptor |
| Signaling Pathway | GPCR/G Protein; Neuronal Signaling |
| Solubility | In Vitro: DMSO: 116.67 mg/mL (367.09 mM; Requires sonication; Hygroscopic DMSO has a significant impact on the solubility of product, please use newly opened DMSO) |
| Storage | 4°C, sealed storage, away from moisture and light. In solvent: -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture and light). |
| 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 | 116.67 mg/mL (367.09 mM) | requires sonication; use freshly opened DMSO (absorbed moisture lowers solubility) |
Aliquot the stock solution and store it at -80°C (up to 6 months) or -20°C (up to 1 month); sealed storage, away from moisture and light; avoid repeated freeze-thaw cycles.
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 (6.54 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 (6.54 mM); clear solution; requires sonication |
| How to prepare | Gives a clear solution at 2.08 mg/mL. 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 (6.54 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
In isolated circumflex coronary artery segments from dogs, Phentolamine hydrochloride (1-100 μM) antagonizes the vasodilatory effect of Cromakalim in a concentration-dependent manner; at 100 μM, it lowers the pD2 value of Cromakalim from 6.62 to 5.08[3].
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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bioRxiv. 2023 Oct 13.
