chir99021 chir99021 chir99021 is a chemical compound which acts as an inhibitor of the enzyme gsk-3. it has proved useful for applications in molecular biology involving the transformation of one cell type to another. chir99021 names iupac name 6-((2-((4-(2,4-dichlorophenyl)-5-(4-methyl-1h-imidazol-2-yl)pyrimidin-2-yl)amino)ethyl)amino)nicotinonitrile identifiers cas number 252917-06-9 y 3d model (jsmol) interactive image echa infocard 100.236.922 pubchem cid 9956119 unii 234cmt4gk4 y comptox dashboard (epa) dtxsid90179931 inchi inchi=1s/c22h18cl2n8/c1-13-10-29-21(31-13)17-12-30-22(32-20(17)16-4-3-15(23)8-18(16)24)27-7-6-26-19-5-2-14(9-25)11-28-19/h2-5,8,10-12h,6-7h2,1h3,(h,26,28)(h,29,31)(h,27,30,32)key: aqgnhmojwbzfqq-uhfffaoysa-n smiles n#cc1=cn=c(nccnc2=nc=c(c3=nc(c)=cn3)c(c4=cc=c(cl)c=c4cl)=n2)c=c1 properties chemical formula c22h18cl2n8 molar mass 465.34 g·mol−1 except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). infobox references a mixture of chir99021 and valproic acid (fx-322) is claimed to increase the proliferation of inner ear stem cells, potentially allowing regrowth of the hair cells which are important for hearing, and are lost through chronic exposure to loud noises or as part of the aging process.