Cat. No.: HY-N0776

Isorhamnetin

(Synonyms: 3'-Methylquercetin)

17 Cited Publications

Customer Review

Based on 17 publication(s) in Google Scholar

Isorhamnetin is a flavonoid compound extracted from the Chinese herb Hippophae rhamnoides L.. Isorhamnetin suppresses skin cancer through direct inhibition of MEK1 and PI3K.

For research use only. We do not sell to patients.

Purity: 99.74%
CAS No.: 480-19-3
Formula: C₁₆H₁₂O₇
Molecular Weight:316.26

Storage:

Powder -20°C, 3 years , 4°C, 2 years ; In solvent -80°C, 1 year , -20°C, 6 months

Isorhamnetin Chemical Structure

CAS No.: 480-19-3

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Biological Activity
- Description
- IC₅₀ & Target
- Cellular Effect
- In Vitro
- In Vivo
Chemical Information
Publications (17)
Solvent & Solubility
- In Vitro
- In Vivo
Protocol
Purity & Documentation
References
Help & FAQs
Bioz

Biological Activity

Description

Isorhamnetin is a flavonoid compound extracted from the Chinese herb Hippophae rhamnoides L.. Isorhamnetin suppresses skin cancer through direct inhibition of MEK1 and PI3K.

IC₅₀ & Target^[1]

MEK1

PI3-K

Human Endogenous Metabolite

All MEK Isoforms :

All PI3K Isoforms :

All Endogenous Metabolite Isoforms :

Cellular Effect

Cell Line	Type	Value	Description	References
HeLa	IC₅₀	≥10 μM Compound: isorhamnetin	Cytotoxicity against human HeLa cells by MTT assay Cytotoxicity against human HeLa cells by MTT assay	[PMID: 19278239]
HeLa	IC₅₀	8.1 μM Compound: Isorhamnetol	Cytotoxicity against human HeLa cells assessed as reduction in cell viability incubated for 48 hrs by MTT assay Cytotoxicity against human HeLa cells assessed as reduction in cell viability incubated for 48 hrs by MTT assay	[PMID: 31784199]
Huh-7	CC₅₀	>50 μM Compound: 27	Cytotoxicity against human Huh7.5.1 cells by MTT assay Cytotoxicity against human Huh7.5.1 cells by MTT assay	[PMID: 22445328]
HUVEC	IC₅₀	2.8 μM Compound: 39, isorhamnetin	Inhibition of NADPH oxidase in Homo sapiens (human) HUVEC cells Inhibition of NADPH oxidase in Homo sapiens (human) HUVEC cells	10.1007/s00044-012-0353-y
MCF7	IC₅₀	10.3 μM Compound: Isorhamnetol	Cytotoxicity against human MCF7 cells assessed as reduction in cell viability incubated for 48 hrs by MTT assay Cytotoxicity against human MCF7 cells assessed as reduction in cell viability incubated for 48 hrs by MTT assay	[PMID: 31784199]
Monocyte	IC₅₀	3.8 μM Compound: isorhamnetin	Inhibition of procoagulant activity in monocyte from human blood assessed as counteraction of IL1-induced tissue factor expression after 18 hrs Inhibition of procoagulant activity in monocyte from human blood assessed as counteraction of IL1-induced tissue factor expression after 18 hrs	[PMID: 8882428]
Monocyte	IC₅₀	3.8 x 10^-6 M Compound: isorhamnetin	Inhibition of procoagulant activity in monocyte from human blood assessed as counteraction of IL1-induced tissue factor expression after 18 hrs Inhibition of procoagulant activity in monocyte from human blood assessed as counteraction of IL1-induced tissue factor expression after 18 hrs	[PMID: 8882428]
N9	IC₅₀	17.87 μM Compound: 1	Antineuroinflammatory activity in mouse N9 cells assessed as inhibition of LPS-induced nitric oxide production after 24 hrs by Griess assay Antineuroinflammatory activity in mouse N9 cells assessed as inhibition of LPS-induced nitric oxide production after 24 hrs by Griess assay	[PMID: 28073678]

In Vitro

Isorhamnetin is a plant flavonoid that occurs in fruits and medicinal herbs. Isorhamnetin binds directly to MEK1 in an ATP-noncompetitive manner and to PI3-K in an ATP-competitive manner. In vitro and ex vivo kinase assay data show that Isorhamnetin inhibits the kinase activity of MAP/ERK kinase (MEK) 1 and PI3-K and the inhibition is due to direct binding with Isorhamnetin^[1]. Isorhamnetin inhibits the Akt/mTOR and MEK/ERK signaling pathways, and promotes the activity of the mitochondrial apoptosis signaling pathway. The inhibitory effects of Isorhamnetin on breast cancer cells are determined using the CCK-8 method. Isorhamnetin inhibits the proliferation of numerous breast cancer cells (IC₅₀, ~10 μM), including MCF7, T47D, BT474, BT-549, MDA-MB-231 and MDA-MB-468, whereas less inhibitory activity is observed in the MCF10A normal breast epithelial cell line (IC₅₀, 38 μM)^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

In Vivo

Photographic data shows that Isorhamnetin treatment suppresses tumor development in mice. The average volume of tumors in untreated mice increases over time and reaches a volume of 623 mm³ at 4 weeks post-inoculation; however, at this time, in mice treated with 1 or 5 mg/kg Isorhamnetin, the average tumor volume is only 280 or 198 mm³, respectively. At the end of the study, Isorhamnetin treatment (1 or 5 mg/kg) reduces tumor weight compared with the untreated control group^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Chemical Information

CAS No. 480-19-3
Appearance Solid
Molecular Weight 316.26
Formula C₁₆H₁₂O₇
Color Light yellow to yellow
SMILES

O=C1C(O)=C(C2=CC=C(O)C(OC)=C2)OC3=CC(O)=CC(O)=C13
Synonyms

3'-Methylquercetin
Structure Classification
- Flavonoids
- Flavonols
- Phenols
- Polyphenols
Initial Source
- Microorganisms
- Endogenous metabolite
Shipping

Room temperature in continental US; may vary elsewhere.

Storage

Powder	-20°C	3 years
	4°C	2 years
In solvent	-80°C	1 year
	-20°C	6 months

Publications (17)

All Cell Proliferation/Viability AssayCell Imaging/StainingIn Vivo Efficacy StudyHistological Imaging/StainingWB

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Journal Impact Factor

Nat Aging

Targeting senescence induced by age or chemotherapy with a polyphenol-rich natural extract improves longevity and healthspan in mice. [Abstract]

2024 Sep;4(9):1231-1248. PMID: 38951692
Acta Pharm Sin B

Chrysin serves as a novel inhibitor of DGK α/FAK interaction to suppress the malignancy of esophageal squamous cell carcinoma (ESCC). [Abstract]

2021 Jan;11(1):143-155. PMID: 33532186
Food Chem

Effects of sun drying combined with baking processes on the flavor quality of Chongqing Tuocha raw tea. [Abstract]

2025 Dec 30:497:146992. PMID: 41285060
Food Chem

Flavonoid-mediated metabolic underpinning quality variation in red bud-sport pear mutants. [Abstract]

2025 May 31:489:144992. PMID: 40466530
Food Chem

Discovery of novel ascorbic acid derivatives and other metabolites in fruit of Rosa roxburghii Tratt through untargeted metabolomics and feature-based molecular networking. [Abstract]

2023 Mar 30;405(Pt A):134807. PMID: 36370576
Phytomedicine

Fangchinoline suppresses nasopharyngeal carcinoma progression by inhibiting SQLE to regulate the PI3K/AKT pathway dysregulation. [Abstract]

2025 May:140:156484. PMID: 40090046
Ind Crops Prod

2025 Dec 11;239:122458.
J Ethnopharmacol

Integrated metabolomics and proteomics analysis elucidated the therapeutic effect of Huangkui Capsule on tacrolimus-induced chronic nephrotoxicity in rats. [Abstract]

2026 Apr 6:360:121196. PMID: 41534748
Bioorg Chem

Identification of FTY720 and COH29 as novel topoisomerase I catalytic inhibitors by experimental and computational studies. [Abstract]

2024 Jun:147:107412. PMID: 38696845
Invest Ophthalmol Vis Sci

Isorhamnetin Ameliorates Aspergillus fumigatus Keratitis by Reducing Fungal Load, Inhibiting Pattern-Recognition Receptors and Inflammatory Cytokines. [Abstract]

2021 Mar 1;62(3):38. PMID: 33783487

Isorhamnetin purchased from MedChemExpress. Usage Cited in: Invest Ophthalmol Vis Sci. 2021 Mar 1;62(3):38. [Abstract]

Fumigatus conidia were cultured with 0.5% DMSO and Isorhamnetin at different concentrations (5–320 μg/mL) for 48 hours. Isorhamnetin started to inhibit the growth of A. fumigatus at 10 μg/mL and prevented 90% of A. fumigatus growth (MIC₉₀) at 80 μg/mL.

Isorhamnetin purchased from MedChemExpress. Usage Cited in: Invest Ophthalmol Vis Sci. 2021 Mar 1;62(3):38. [Abstract]

Hyphae treated with 0.5% DMSO showed an intact morphological structure characterized by smooth surface and rounded mycelia. Isorhamnetin (80 μg/mL; 24 h) treatment caused the hyphae of A. fumigatus to become thinner, swollen, twisted, and knotted.

Isorhamnetin purchased from MedChemExpress. Usage Cited in: Invest Ophthalmol Vis Sci. 2021 Mar 1;62(3):38. [Abstract]

Representative slit lamp photographs and clinical scores of DMSO or Isorhamnetin (5 µL; 80 µg/mL; four times daily for five days) treated A. fumigatus keratitis mice at days 1, 3, and 5. Isorhamnetin treatment made the corneas of mice more transparent, with smaller ulcers and no perforation, and also significantly decreased the clinical score at 3 and 5 days.

Isorhamnetin purchased from MedChemExpress. Usage Cited in: Invest Ophthalmol Vis Sci. 2021 Mar 1;62(3):38. [Abstract]

PAS staining of corneal tissue sections (magnification × 400) of DMSO or Isorhamnetin (5 µL; 80 µg/mL; four times daily for five days) treated. Isorhamnetin observably reduced fungal hyphal load and alleviated corneal edema in A. fumigatus–infected mice on the third day after.

Isorhamnetin purchased from MedChemExpress. Usage Cited in: Invest Ophthalmol Vis Sci. 2021 Mar 1;62(3):38. [Abstract]

Western blot results and grayscale analysis of TLR-2, TLR-4, Dectin-1 at 3 days p.i. Isorhamnetin (5 µL; 80 µg/mL; four times daily) significantly inhibited A. fumigatus induction of TLR-2, TLR-4 and Dectin-1 in protein level.
Biol Proced Online

Network Pharmacology and Experimental Validation Reveal Aidi Injection Suppresses Prostate Cancer via EGFR Inhibition and STAT3-Mediated Apoptosis. [Abstract]

2025 Dec 22;27(1):48. PMID: 41430119
Sci Rep

Active ingredients Isorhamnetin of Croci Srigma inhibit stomach adenocarcinomas progression by MAPK/mTOR signaling pathway. [Abstract]

2023 Aug 3;13(1):12607. PMID: 37537191
BMC Complement Med Ther

Network pharmacology-based strategy to investigate the bioactive ingredients and molecular mechanism of Evodia rutaecarpa in colorectal cancer. [Abstract]

2023 Dec 1;23(1):433. PMID: 38041080
Front Cardiovasc Med

Exploring the Mechanism of Hawthorn Leaves Against Coronary Heart Disease Using Network Pharmacology and Molecular Docking. [Abstract]

2022 Jun 16:9:804801. PMID: 35783840
Vet Microbiol

The Chinese medicine monomer Schisandrin C inhibits PRRSV infection by regulating the OGT-PI3K/AKT/mTOR signaling pathway. [Abstract]

2026 May:316:110992. PMID: 41865607
Exp Eye Res

Isorhamnetin suppresses the epithelial-mesenchymal transition of the retinal pigment epithelium both in vivo and in vitro through Nrf2-dependent AKT/GSK-3β pathway. [Abstract]

2024 Mar:240:109823. PMID: 38331017
Cell Biochem Biophys

Pro-differentiative, Pro-adhesive and Pro-migratory Activities of Isorhamnetin in MC3T3-E1 Osteoblasts via Activation of ERK-dependent BMP2-Smad Signaling. [Abstract]

2024 Dec;82(4):3607-3617. PMID: 39136840

Solvent & Solubility

In Vitro:

DMSO : 100 mg/mL (316.20 mM; Need ultrasonic; Hygroscopic DMSO has a significant impact on the solubility of product, please use newly opened DMSO)

View the Complete Stock Solution Preparation Table

Preparing Stock Solutions

View the Complete Stock Solution Preparation Table

Concentration Solvent Mass

1 mg

5 mg

10 mg

Concentration

Solvent

Mass

1 mM

3.1620 mL

15.8098 mL

31.6196 mL

5 mM

0.6324 mL

3.1620 mL

6.3239 mL

10 mM

0.3162 mL

1.5810 mL

3.1620 mL

Please refer to the solubility information to select the appropriate solvent. Once prepared, please aliquot and store the solution to prevent product inactivation from repeated freeze-thaw cycles.

Storage method and period of stock solution: -80°C, 1 year; -20°C, 6 months. When stored at -80°C, please use it within 1 year. When stored at -20°C, please use it within 6 months.

Molarity Calculator

Mass (g) = Concentration (mol/L) × Volume (L) × Molecular Weight (g/mol)

Mass Mass

Concentration Concentration

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Molecular Weight Molecular Weight

Dilution Calculator

Concentration _(start) × Volume _(start) = Concentration _(final) × Volume _(final)

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In Vivo:

Select the appropriate dissolution method based on your experimental animal and administration route.

Stock Solution Working Solution

For the following dissolution methods, please ensure to first prepare a clear stock solution using an In Vitro approach and then sequentially add co-solvents:
To ensure reliable experimental results, the clarified stock solution can be appropriately stored based on storage conditions. As for the working solution for In Vivo experiments, it is recommended to prepare freshly and use it on the same day.
The percentages shown for the solvents indicate their volumetric ratio in the final prepared solution. If precipitation or phase separation occurs during preparation, heat and/or sonication can be used to aid dissolution.

Protocol 1

Add each solvent one by one: 10% DMSO 40% PEG300 5% Tween-80 45% Saline

Solubility: 2.08 mg/mL (6.58 mM); Suspended solution; Need ultrasonic

This protocol yields a suspended solution of 2.08 mg/mL. Suspended solution can be used for oral and intraperitoneal injection.

Taking 1 mL working solution as an example, add 100 μL DMSO stock solution (20.8 mg/mL) to 400 μL PEG300, and mix evenly; then add 50 μL Tween-80 and mix evenly; then add 450 μL Saline to adjust the volume to 1 mL.

In Vivo Dissolution Calculator

Please enter the basic information of animal experiments:

Dosage Dosage
mg/kg
Animal Weight (Per Animal) Animal Weight (Per Animal)
g
Dosing Volume (Per Animal) Dosing Volume (Per Animal)
μL
Number of Animals Number of Animals

Recommended: Prepare an additional quantity of animals to account for potential losses during experiments.

Recommended: Prepare an additional quantity of animals to account for potential losses during experiments.

Please enter your animal formula composition:

%
DMSO +

Recommended: Keep the proportion of DMSO in working solution below 2% if your animal is weak.
%
+
+
%
Tween-80 + +
%
Saline +

The co-solvents required include: DMSO, . All of co-solvents are available by MedChemExpress (MCE). , Tween 80. All of co-solvents are available by MedChemExpress (MCE).

Working solution concentration: 0.22 mg/mL

Protocol

Cell Assay^[2]

MCF7, T47D, BT474, BT-549, MDA-MB-231 and MDA-MB-468 breast cancer cell lines, as well as a MCF10A normal breast epithelial cell line (control) are seeded into 96-well plates at a density of 5×10³ cells/well in 100 µL DMEM and placed in cell incubator for 12 h at 37°C in an atmosphere containing 5% CO₂. The cells are then treated with various concentrations of Isorhamnetin (100, 33.3, 11.1, 3.7, 1.2, 0.4 and 0 µM) for 48 h, and cell proliferation rates are determined by adding 10 µL CCK-8 solution prior to incubation at 37°C for 2 h. The absorbance is measured at a wavelength of 450 nm using a SpectraMax 190 Microplate Reader. For each assay, four parallel wells are included, and the half maximal inhibitory concentration (IC₅₀) is measured using the inhibition curve and presented as the mean of three independent experiments^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Animal Administration^[1]

Mice^[1]
Female athymic nude mice are injected subcutaneously in the flank with A431 cells (1×10⁶ cells in 50 μL of medium and 50 μL of Matrigel). Cells are allowed to form tumors, and once the tumors reach a size of 40 mm³, the mice are randomly assigned into groups (6 mice/group) and treated with (1 or 5 mg/kg body weight) or without Isorhamnetin in 40% DMSO/PBS buffer, administered intraperitoneally every other day for 28 days. Tumor size is measured every week with calipers, and the tumor volume is calculated. Mice are sacrificed after 28 days of treatment when the control tumors reach approximately 600 mm³. The tumors are harvested, photographed, and weighed. Tumor tissues are used for western blot analysis and immunohistochemical analysis.

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Purity & Documentation

Select Batch:

Purity: 99.98%

Assay: 99.98%

ee.: 99.98%

Data Sheet (280 KB)
SDS (418 KB)
- English - EN (418 KB)
- Français - FR (418 KB)
- Deutsch - DE (418 KB)
- Norwegian - NO (418 KB)
- Español - ES (418 KB)
- Swedish - SV (418 KB)
- Italian - IT (418 KB)
- Portuguese - PT (418 KB)
COA (2659 KB)
Elemental Analysis Report (2659 KB)
HNMR (2659 KB)
CNMR (2659 KB)
RP-HPLC (2659 KB)
NP-HPLC (2659 KB)
MS (2659 KB)
LCMS (2659 KB)
IR (2659 KB)
GC (2659 KB)
OR (2659 KB)
SDS-PAGE (2659 KB)
SEC-HPLC (2659 KB)
Other Report (2659 KB)
Handling Instructions (2659 KB)

References

[1]. Kim JE, et al. Isorhamnetin suppresses skin cancer through direct inhibition of MEK1 and PI3-K. Cancer Prev Res (Phila). 2011 Apr;4(4):582-91. [Content Brief]

[2]. Hu S, et al. Isorhamnetin inhibits cell proliferation and induces apoptosis in breast cancer via Akt and mitogen activated protein kinase kinase signaling pathways. Mol Med Rep. 2015 Nov;12(5):6745-51. [Content Brief]

Help & FAQs

How should lyophilized recombinant proteins be reconstituted and stored?

1. Before opening the cap, centrifuge the vial at 13000 rpm for 20-30 seconds. This step will ensure that any lyophilized powder that may have adhered to the cap or walls is collected at the bottom of the vial, minimizing the risk of product loss.

Complete Stock Solution Preparation Table

Storage method and period of stock solution: -80°C, 1 year; -20°C, 6 months. When stored at -80°C, please use it within 1 year. When stored at -20°C, please use it within 6 months.

Optional Solvent	Concentration Solvent Mass	1 mg	5 mg	10 mg	25 mg
DMSO	1 mM	3.1620 mL	15.8098 mL	31.6196 mL	79.0489 mL
	5 mM	0.6324 mL	3.1620 mL	6.3239 mL	15.8098 mL
	10 mM	0.3162 mL	1.5810 mL	3.1620 mL	7.9049 mL
	15 mM	0.2108 mL	1.0540 mL	2.1080 mL	5.2699 mL
	20 mM	0.1581 mL	0.7905 mL	1.5810 mL	3.9524 mL
	25 mM	0.1265 mL	0.6324 mL	1.2648 mL	3.1620 mL
	30 mM	0.1054 mL	0.5270 mL	1.0540 mL	2.6350 mL
	40 mM	0.0790 mL	0.3952 mL	0.7905 mL	1.9762 mL
	50 mM	0.0632 mL	0.3162 mL	0.6324 mL	1.5810 mL
	60 mM	0.0527 mL	0.2635 mL	0.5270 mL	1.3175 mL
	80 mM	0.0395 mL	0.1976 mL	0.3952 mL	0.9881 mL
	100 mM	0.0316 mL	0.1581 mL	0.3162 mL	0.7905 mL

Keywords

Isorhamnetin

17 Cited Publications

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Isorhamnetin

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Publications Citing Use of MedChemExpress (MCE) Isorhamnetin

All MEK Isoforms

All PI3K Isoforms

All Endogenous Metabolite Isoforms

Biological Activity