T5648 Sigma-Aldrich



Synonym: (Z)-1-(p-Dimethylaminoethoxyphenyl)-1,2-diphenyl-1-butene, trans-2-[4-(1,2-Diphenyl-1-butenyl)phenoxy]-N,N-dimethylethylamine



Related Categories Antibiotics, Antibiotics A to Z, Antibiotics T-Z, Antibiotics by Application, Antineoplastic and Immunosuppressive Antibiotics,
assay   ≥99%
mp   97-98 °C (lit.)
solubility   H2O: insoluble <0.1% at 20 °C
  chloroform: soluble 50 mg/mL, clear, colorless to faintly yellow
  2-propanol: soluble
  DMSO: soluble
  ethanol: soluble
  methanol: soluble
  propylene glycol: soluble
Mode of action   enzyme | inhibits
antibiotic activity spectrum   neoplastics
originator   AstraZeneca
storage temp.   2-8°C
SMILES string   CC\C(c1ccccc1)=C(/c2ccccc2)c3ccc(OCCN(C)C)cc3
InChI   1S/C26H29NO/c1-4-25(21-11-7-5-8-12-21)26(22-13-9-6-10-14-22)23-15-17-24(18-16-23)28-20-19-27(2)3/h5-18H,4,19-20H2,1-3H3/b26-25-
Gene Information   human ... CYP1A2(1544), EBP(10682), ESR1(2099), ESR2(2100), ESRRA(2101)
rat ... Ar(24208), Esr1(24890)


General description

Tamoxifen is a selective estrogen response modifier (SERM), protein kinase C inhibitor and anti-angiogenetic factor. Tamoxifen is a prodrug that is metabolized to active metabolites 4-hydroxytamoxifen (4-OHT) and endoxifen by cytochrome P450 isoforms CYP2D6 and CYP3A4. In breast cancer, the gene repressor activity of tamoxifen against ERBB2 is dependent upon PAX2. Blocks estradiol-stimulated VEGF production in breast tumor cells.


Tamoxifen has been used to facilitate the recombination of ect2flox allele in mouse organs91. It has also been used to study its effect on lipopolysaccharide (LPS)-induced microglial activation92.


1, 5 g in glass bottle

Biochem/physiol Actions

Protein kinase C inhibitor. Induces apoptosis in human malignant glioma cell lines. Tamoxifen and its metabolite 4-hydroxytamoxifen are selective estrogen response modifiers (SERMs) that act as estrogen antagonists in mammary gland. Blocks estradiol-stimulated VEGF production in breast tumor cells.

Features and Benefits

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Preparation Note

Tamoxifen is soluble in chloroform at 50 mg/ml and yields a clear, colorless to faint yellow solution. It is also soluble in methanol, ethanol, 2-propanol and propylene glycol. Stock solutions of tamoxifen can also be prepared in DMSO at 10 mM. However, it is practically insoluble in water (solubility is <0.01%, 20° C). Solutions are sensitive to UV light, and DMSO solutions are stable when stored at -20° C in the dark.

Legal Information

LOPAC is a registered trademark of Sigma-Aldrich Co. LLC

Safety & Documentation

Safety Information

Signal word 
Hazard statements 
Precautionary statements 
NONH for all modes of transport
WGK Germany 
Flash Point(F) 
Not applicable
Flash Point(C) 
Not applicable

Frequently Asked Questions

Which document(s) contains shelf-life or expiration date information for a given product?
If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.
How do I get lot-specific information or a Certificate of Analysis?
The lot specific COA document can be found by entering the lot number above under the "Documents" section.
How do I find price and availability?
There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote. USA customers: 1-800-325-3010 or view local office numbers.
What is the Department of Transportation shipping information for this product?
Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.
What is the solubility of tamoxifen, Product No. T5648?
Tamoxifen is tested for solubility in chloroform at a concentration of 50mg/mL.This yields a colorless to faint yellow solution.Tamoxifen is practically insoluble in water.It has been reported to be soluble in methanol, ethanol, 2-propanol and propylene glycol.This product is also reported to be soluble in DMSO at 10mM concentration.Reference for DMSO solubility: Wong, K.R., et al., Am. J. Physiol. Heart Circ. Physiol., 277, H1403-H1409 (1999).Please also see the product information sheet (under Documents, above) for more information on the solubility of this product.
What is the stability of tamoxifen (e.g., Product No. T5648) once in solution?
Solutions of tamoxifen are sensitive to UV light. According to C.A. O'Brian et al., [Cancer Res. 45, 2462 (1985)], tamoxifen when dissolved in DMSO can be stored at -20°C in the dark. We generally recommend making the solution fresh right before each use.
How do I find the expiration date of the bottle of Product No T5648, Tamoxifen,in my possession?
According to Sigma Quality Control Data, T5648 (tamoxifen) should be stable for at least two years if stored dessicated at 2-8°C in the dark.However, there is not an established expiration or retest date for Tamoxifen.This product is guaranteed for 1 year from shipment, if stored correctly and unopened.
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