Elacestrant S enantiomer di-HCl (RAD1901 S enantiomer di-HCl) is the less active enantiomer of Elacestrant. Elacestrant (RAD1901) di-HCl is a selective and orally bioactive estrogen receptor (ER) degrader with IC50s of 48 and 870 nM for ERα and ERβ, respectively.

Physicochemical Properties

Molecular Formula	C30H40CL2N2O2
Molecular Weight	531.5568
Exact Mass	530.246
Elemental Analysis	C, 78.56; H, 8.35; N, 6.11; O, 6.98
CAS #	2309762-30-7
Related CAS #	Elacestrant;722533-56-4;Elacestrant dihydrochloride;1349723-93-8;Elacestrant (S enantiomer);2309762-29-4
PubChem CID	127020970
Appearance	White to off-white solid powder
Hydrogen Bond Donor Count	4
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	10
Heavy Atom Count	36
Complexity	578
Defined Atom Stereocenter Count	1
SMILES	Cl[H].Cl[H].O([H])C1C([H])=C([H])C2=C(C=1[H])C([H])([H])C([H])([H])[C@]([H])(C1C([H])=C([H])C(=C([H])C=1N(C([H])([H])C([H])([H])[H])C([H])([H])C1C([H])=C([H])C(C([H])([H])C([H])([H])N([H])C([H])([H])C([H])([H])[H])=C([H])C=1[H])OC([H])([H])[H])C2([H])[H]
InChi Key	XGFHYCAZOCBCRQ-ROPHLPQBSA-N
InChi Code	InChI=1S/C30H38N2O2.2ClH/c1-4-31-17-16-22-6-8-23(9-7-22)21-32(5-2)30-20-28(34-3)14-15-29(30)26-11-10-25-19-27(33)13-12-24(25)18-26;;/h6-9,12-15,19-20,26,31,33H,4-5,10-11,16-18,21H2,1-3H3;2*1H/t26-;;/m0../s1
Chemical Name	(6S)-6-[2-[ethyl-[[4-[2-(ethylamino)ethyl]phenyl]methyl]amino]-4-methoxyphenyl]-5,6,7,8-tetrahydronaphthalen-2-ol;dihydrochloride
Synonyms	Elacestrant S enantiomer dihydrochloride; 2309762-30-7; Elacestrant (S enantiomer dihydrochloride); (6S)-6-[2-[ethyl-[[4-[2-(ethylamino)ethyl]phenyl]methyl]amino]-4-methoxyphenyl]-5,6,7,8-tetrahydronaphthalen-2-ol;dihydrochloride; RAD1901 S enantiomer dihydrochloride;
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 Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.
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

Targets	ERα/ERβ
References	[1]. RAD1901: a novel, orally bioavailable selective estrogen receptor degrader that demonstrates antitumor activity in breast cancer xenograft models. Anticancer Drugs. 2015 Oct;26(9):948-56.
Additional Infomation	Agents that inhibit estrogen production, such as aromatase inhibitors or those that directly block estrogen receptor (ER) activity, such as selective estrogen receptor modulators and selective estrogen receptor degraders, are routinely used in the treatment of ER-positive breast cancers. However, although initial treatment with these agents is often successful, many women eventually relapse with drug-resistant breast cancers. To overcome some of the challenges associated with current endocrine therapies and to combat the development of resistance, there is a need for more durable and more effective ER-targeted therapies. Here we describe and characterize a novel, orally bioavailable small-molecule selective estrogen receptor degrader, RAD1901, and evaluate its therapeutic potential for the treatment of breast cancer. RAD1901 selectively binds to and degrades the ER and is a potent antagonist of ER-positive breast cancer cell proliferation. Importantly, RAD1901 produced a robust and profound inhibition of tumor growth in MCF-7 xenograft models. In an intracranial MCF-7 model, RAD1901-treated animals survived longer than those treated with either control or fulvestrant, suggesting the potential benefit of RAD1901 in the treatment of ER-positive breast cancer that has metastasized to the brain. Finally, RAD1901 preserved ovariectomy-induced bone loss and prevented the uterotropic effects of E2, suggesting that it may act selectively as an agonist in bone but as an antagonist in breast and uterine tissues. RAD1901 is currently under clinical study in postmenopausal women with ER-positive advanced breast cancer.[1]

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	1.8813 mL	9.4063 mL	18.8126 mL
	5 mM	0.3763 mL	1.8813 mL	3.7625 mL
	10 mM	0.1881 mL	0.9406 mL	1.8813 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.