Adarotene (ST-1926), a synthetic, phenolic hydroxyl retinoid with proapoptotic activity, is an atypical retinoid and a promising anti-tumour agent with selective apoptotic activity on the leukaemic blast. The anti-tumour activity of the compound has been associated with its capacity to induce DNA double stranded breaks. ( Eur J Cancer. 2012 Dec 11. S0959-8049(12)00909-4.).

Physicochemical Properties

Molecular Formula	C25H26O3
Molecular Weight	374.4721
Exact Mass	374.188
CAS #	496868-77-0
PubChem CID	9864378
Appearance	White to green solid powder
LogP	5.624
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	3
Rotatable Bond Count	4
Heavy Atom Count	28
Complexity	574
Defined Atom Stereocenter Count	0
SMILES	C1C2CC3CC1CC(C2)(C3)C4=C(C=CC(=C4)C5=CC=C(C=C5)/C=C/C(=O)O)O
InChi Key	QAWBIEIZDDIEMW-RXJOCBMKSA-N
InChi Code	InChI=1S/C25H26O3/c26-23-7-6-21(20-4-1-16(2-5-20)3-8-24(27)28)12-22(23)25-13-17-9-18(14-25)11-19(10-17)15-25/h1-8,12,17-19,26H,9-11,13-15H2,(H,27,28)/b8-3+/t17-,18+,19-,25?
Chemical Name	(E)-3-(3'-((3r,5r,7r)-adamantan-1-yl)-4'-hydroxy-[1,1'-biphenyl]-4-yl)acrylic acid
Synonyms	ST1926 ST 1926 ST-1926
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	Adarotene, with an IC50 ranging from 0.1 to 0.3 µM, inhibits the development of numerous human tumor cell lines in a dose-dependent manner. Depending on the tumor cells IGROV-1 and DU145, adarotene induces cells to accumulate in the G1/S or S phase of the cell cycle [1]. Adarotene exhibits apoptotic and cytotoxic properties against a range of leukemia and cancerous cells, including recently isolated AML blasts in primary culture. The ligand-binding domain of RARγ is similar to the molecular target of ST1926's apoptotic action in myeloid leukemia cells. When cells are treated with alpha-adarotene, intracellular calcium accumulates quickly [2].
ln Vivo	In nude mice, adarotene (15, 20 mg/kg, orally administered) can considerably suppress the formation of tumors in human ovarian cancer A2780/DX and human melanoma MeWo [1]. Oral administration of adarotene (30, 40 mg/kg) has been shown to significantly and dose-dependently prolong the longevity of SCID mice harboring NB4 without evident harm [2].
References	[1]. A novel atypical retinoid endowed with proapoptotic and antitumor activity. J Med Chem. 2003 Mar 13;46(6):909-12. [2]. ST1926, a novel and orally active retinoid-related molecule inducing apoptosis in myeloid leukemia cells: modulation of intracellular calcium homeostasis. Blood. 2004 Jan 1;103(1):194-207.
Additional Infomation	Adarotene is a synthetic, phenolic hydroxyl retinoid with proapoptotic activity. As an atypical retinoid, adarotene has the ability to induce apoptosis which is independent of retinoid receptor signaling.

Solubility Data

Solubility (In Vitro)

DMSO : ~25 mg/mL (~66.76 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (6.68 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.5 mg/mL (6.68 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. 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.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.6704 mL	13.3522 mL	26.7044 mL
	5 mM	0.5341 mL	2.6704 mL	5.3409 mL
	10 mM	0.2670 mL	1.3352 mL	2.6704 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.