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STO-609 acetate

Catalog No.
Ca2+-calmodulin-dependent protein kinase kinase inhibitor
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Ship with 5-10 days
Ship with 5-10 days
Ship with 5-10 days

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STO-609 acetate is a specific inhibitor of the Ca2+/calmodulin-dependent protein kinase kinase (CaM-KK), with Ki values of 80 and 15 ng/ml against CaM-KKα and CaM-KKβ isoforms, respectively [1]. 

CaM-KKα and CaM-KKβ, highly expressed in the brain with the α isoform also expressed in various peripheral tissues such as thymus and spleen in mammals, belongs to Ca2+/calmodulin-dependent protein kinases, which are involved in many cellular responses mediated by an increase in the concentration of intracellular calcium [1]. 

STO-609 exhibited high selectivity for CaM-KK without significantly affecting the downstream CaM kinases (CaM-KI and -IV), and the IC50 value of STO-609 against CaM-KII was ~ 10 μg/ml. In transfected HeLa cells, STO-609 (0.01 ~ 10 μg/ml) suppressed the Ca2+-induced activation of CaM-KIV in a dose-dependent manner. In addition, in SH-SY5Y neuroblastoma cells, STO-609 at a concentration of 1 μg/ml significantly reduced the endogenous activity of CaM-KK [1]. 

In ovariectomized mice, in vivo administration of STO-609 (10 μM, 200 μl per mouse, i.p., thrice a week) resulted in increased osteoblasts and diminished osteoclasts, significantly protect adult mice from ovariectomy-induced osteoporosis [2]. 


[1]. Tokumitsu H, Inuzuka H, Ishikawa Y, et al. STO-609, a specific inhibitor of the Ca(2+)/calmodulin-dependent protein kinase kinase. Journal of Biological Chemistry, 2002, 277(18): 15813-15818.

[2]. Cary R L, Waddell S, Racioppi L, et al. Inhibition of Ca²⁺/calmodulin-dependent protein kinase kinase 2 stimulates osteoblast formation and inhibits osteoclast differentiation. Journal of Bone and Mineral Research, 2013, 28(7): 1599-1610.

Chemical Properties

Physical AppearanceA crystalline solid
StorageStore at -20°C
Cas No.1173022-21-3
SolubilitySoluble in DMSO
Chemical Name7-oxo-7H-benzo[de]benzo[4,5]imidazo[2,1-a]isoquinoline-3-carboxylic acid compound with acetic acid (1:1)
SDFDownload SDF
Canonical SMILESO=C1N2C(C3=CC=C(C(O)=O)C4=CC=CC1=C34)=NC5=CC=CC=C25.OC(C)=O
Shipping ConditionEvaluation sample solution: ship with blue ice. All other available sizes: ship with RT, or blue ice upon request.
General tipsFor obtaining a higher solubility, please warm the tube at 37°C and shake it in the ultrasonic bath for a while. Stock solution can be stored below -20°C for several months.

Quality Control

Quality Control & MSDS

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Chemical structure

STO-609 acetate