CHIR99021 (CT99021), is also known as 6-[[2-[[4-(2,4-Dichlorophenyl)-5-(5-methyl-1H-imidazol-2-yl)-2-pyrimidinyl]amino]ethyl]amino]-3-pyridinecarbonitrile and CT99021. It is the most potent and selective inhibitor of GSK3. CHIR99021 is an aminopyrimidine derivative. It inhibits GSK3 β and GSK3 α. It also functions as a WNT activator. It is the most selective inhibitor of GSK3 reported so far.
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What is inhibitor CHIR99021? CHIR99021 (CT99021), is also known as 6-[[2-[[4-(2,4-Dichlorophenyl)-5-(5-methyl-1H-imidazol-2-yl)-2-pyrimidinyl]amino]ethyl]amino]-3-pyridinecarbonitrile and CT99021. It is the most potent and selective inhibitor of GSK3. CHIR99021 is an aminopyrimidine derivative. It inhibits GSK3 β and GSK3 α. It also functions as a WNT activator. It is the most selective inhibitor of GSK3 reported so far. What is the mechanism of action of CHIR99021? CHIR99021 activates Wnt-signaling by binding secreted Wnt-protein to its receptor. Disheveled (Dvl/Dsh) is recruited and inhibits the GSK3 (Glycogen Synthase Kinase 3) located in the beta-catenin destruction complex. This leads to an accumulation of free non-phosphorylated beta-catenin in the cytosol. This then translocates to the nucleus and transactivates Wnt-target genes together with the T-cell factor (TCF)/lymphoid-enhancing factor (LEF) family of transcription factors. Thus, chemical inhibition of the GSK3 leads to a pharmacological activation of the canonical Wnt-signaling pathway. What is Glycogen Synthase Kinase 3 (GSK3)? Glycogen synthase kinase 3 (GSK3) is a conserved signaling molecule. It has essential roles in diverse biological processes. GSK3 activity has been linked to a variety of human diseases. They include diabetes, obesity, inflammation, neurodegenerative and psychiatric disorders. Inhibiting GSK3 activity has become an attractive target to be used in the development of treatment strategies for neurodegenerative and psychiatric disorders.

- Differentiation of cells from human embryonic stem (ES) cells and induced pluripotent stem (iPS) cells.
- Used in maintaining mouse ES cells. Maintains human and mouse hematopoietic stem cells in cytokine-free conditions in combination with rapamycin.
- Enables chemical and lineage reprogramming of various cells.
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