Bexirestrant is an orally bioactive ER-α degrader. Bexirestrant can be used for anti-estrogen and anti-tumor research.

Physicochemical Properties

Molecular Formula	C29H26F3NO2
Molecular Weight	477.52
Exact Mass	477.191
CAS #	2505067-70-7
PubChem CID	155770216
Appearance	White to off-white solid powder
LogP	5.7
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	6
Heavy Atom Count	35
Complexity	764
Defined Atom Stereocenter Count	1
SMILES	CC1=C([C@@H](OC2=C1C=CC(=C2)O)C3=CC=C(C=C3)/C=C/CN4CC(C4)CF)C5=CC(=CC(=C5)F)F
InChi Key	DVZLOPUYTKPWHJ-MPWQXXDYSA-N
InChi Code	InChI=1S/C29H26F3NO2/c1-18-26-9-8-25(34)14-27(26)35-29(28(18)22-11-23(31)13-24(32)12-22)21-6-4-19(5-7-21)3-2-10-33-16-20(15-30)17-33/h2-9,11-14,20,29,34H,10,15-17H2,1H3/b3-2+/t29-/m0/s1
Chemical Name	(2S)-3-(3,5-difluorophenyl)-2-[4-[(E)-3-[3-(fluoromethyl)azetidin-1-yl]prop-1-enyl]phenyl]-4-methyl-2H-chromen-7-ol
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
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

ln Vitro	Bexirestrant (compound Formula Ia) has IC50s of 0.3 and suppresses the proliferation of MCF-7 cells that are mutated in Y537S, D538G, and wild type (WT). 2.2 nM and 6.0 nM, respectively[1]. In MCF-7 cells with Y537S, D538G, and WT mutations, bexirestrant causes ER-α degradation with IC50s of 0.3. In that order, 19.6, 12.7 nM[1]. In WT MCF-7 cells, bexirestrant demonstrates 16.3% ER-α persisting at a dose of 1 nM[1].
ln Vivo	In an MCF-Y537S xenograft, bexirestrant (50 mg/kg; po; 28 days) exhibits good efficacy[1]. At 50 mg/kg po dosage, the following pharmacokinetic characteristics were measured in rats: Tmax (h), Cmax (ng/mL), AUClast (hr× ng/mL), AUCinf_obs (hr× ng/mL), T1/2 (h) 4.00 343 7582 9804 26
Animal Protocol	Animal/Disease Models: Female athymic nude mice harboring subcutaneous (sc) MCF7-Y537S xenograft[1] Doses: 50mg/kg Route of Administration: po for 28 days Experimental Results: demonstrated 56% tumor growth inhibition compared to vehicle group after 28 days.
References	[1]. Selective estrogen receptor degrader. WO2021014386 A1. [2]. WHO Drug Information, Vol. 35, No. 4, 2021. Geneva: World Health Organization; 2022.
Additional Infomation	Bexirestrant is an orally bioavailable selective estrogen receptor degrader/downregulator (SERD), with potential antineoplastic activity. Upon oral administration, bexirestrant specifically targets and binds to both wild-type and mutant forms of the estrogen receptor (ER; ERalpha), including the somatic mutations Y537S and D538G. This induces a conformational change that results in ER degradation. This prevents ER-mediated signaling and inhibits both the growth and survival of ER-expressing cancer cells. Somatic mutations in the ER gene ESR1, especially Y537S and D538G, have been associated with acquired antiestrogen drug resistance.

Solubility Data

Solubility (In Vitro)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Solubility (In Vivo)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.0942 mL	10.4708 mL	20.9415 mL
	5 mM	0.4188 mL	2.0942 mL	4.1883 mL
	10 mM	0.2094 mL	1.0471 mL	2.0942 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.