PROTAC KSP-IN-1 (Compound 21) is a PROTAC degrader of kinesin (KSP) that degrades KSP in HCT-116 with a DC50 of 114.8 nM. PROTAC KSP-IN-1 inhibits the proliferation of HCT-116 with an IC50 of 10 nM, arrests the cell cycle of HCT-116 at the G2/M phase, and induces apoptosis in HCT-116. PROTAC KSP-IN-1 exhibits antitumor activity in mouse models. (Blue: Ligand for E3 Ligase Cereblon; Blank: Linker; Pink: Target Protein Ligand)

Physicochemical Properties

Molecular Formula	C48H51N5O8S
Molecular Weight	858.01
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

Targets	KSP 114.8 nM (DC50)
References	[1]. Discovery of novel KSP-targeting PROTACs with potent antitumor effects in vitro and in vivo. Eur J Med Chem. 2025 Jan 15;282:117052.

Solubility Data

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	1.1655 mL	5.8274 mL	11.6549 mL
	5 mM	0.2331 mL	1.1655 mL	2.3310 mL
	10 mM	0.1165 mL	0.5827 mL	1.1655 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.