KS15 is an inhibitor (blocker/antagonist) of the interaction between cryptochromes (CRYs: CRY1 and CRY2) and the CLOCK:BMAL1 heterodimer. KS15 disrupts the feedback effect of CRYs on E-box-dependent transcription through the CLOCK:BMAL1 heterodimer, an indispensable transcriptional regulator of the mammalian circadian clock (EC50=4.9 μM). KS15 has antiproliferation effects.

Physicochemical Properties

Molecular Formula	C20H22BRNO4
Molecular Weight	420.30
Exact Mass	419.073
CAS #	1033781-20-2
PubChem CID	25114872
Appearance	White to off-white solid powder
LogP	4.5
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	5
Rotatable Bond Count	9
Heavy Atom Count	26
Complexity	463
Defined Atom Stereocenter Count	1
SMILES	C1=CC=C(C=C1C[C@H](C(=O)O)OCC)/C(/C)=N/OCC1=CC=C(C=C1)Br
InChi Key	GWSVRVKPZVYTCS-VZMFNRANSA-N
InChi Code	InChI=1S/C20H22BrNO4/c1-3-25-19(20(23)24)12-16-5-4-6-17(11-16)14(2)22-26-13-15-7-9-18(21)10-8-15/h4-11,19H,3,12-13H2,1-2H3,(H,23,24)/b22-14+/t19-/m1/s1
Chemical Name	(2R)-3-[3-[(E)-N-[(4-bromophenyl)methoxy]-C-methylcarbonimidoyl]phenyl]-2-ethoxypropanoic acid
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

ln Vitro

The restoration of E-box-driven luciferase activity was observed at varying dosages of KS15, ranging from μM to 10 μM. This suggests that KS15 carries the transcriptional effects of CRY CLOCK:BMAL1 reversal regulation. The C-terminal region of cryptochromes (CRYs: CRY1 and CRY2) is directly bound by KS15, which also increases E-box-mediated transcription. This results in a considerable inhibition of transcription between CRYs and BMAL1 [2]. Cell development is slowed by KS15. MCF-7 cells' speed and chemical strength are increased in response to doxorubicin and tamoxifen. For some forms of breast cancer, KS15 improves the hardness of anti-tumor medications and has anti-ischemic properties [2].

References

[1]. A synthetic cryptochrome inhibitor induces anti-proliferative effects and increases chemosensitivity in human breast cancer cells. Biochem Biophys Res Commun. 2015;467(2):441-446. [2]. The cryptochrome inhibitor KS15 enhances E-box-mediated transcription by disrupting the feedback action of a circadian transcription-repressor complex. Life Sci. 2018;200:49-55.

Solubility Data

Solubility (In Vitro)

DMSO : ~100 mg/mL (~237.93 mM) H2O : < 0.1 mg/mL

Solubility (In Vivo)

Solubility in Formulation 1: 2.5 mg/mL (5.95 mM) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), suspension solution; with sonication. 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 (5.95 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication. 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. Solubility in Formulation 3: ≥ 2.5 mg/mL (5.95 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (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 corn oil and mix evenly.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.3793 mL	11.8963 mL	23.7925 mL
	5 mM	0.4759 mL	2.3793 mL	4.7585 mL
	10 mM	0.2379 mL	1.1896 mL	2.3793 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.