Protein Kinase Inhibitor H-89 (PKI) (N-(2-p-bromocinnamylaminoethyl]-5-isoquinolinesulfonamide)

Protein Kinase Inhibitors, The newly synthesized isoquinolinesulfonamide derivatives KN-62, KN-04, H-89, H-88, H-85, CKI-7, and CKI-8, as well as methoxybenzenesulfonamide derivatives KN-93 and KN-92 are protein kinase inhibitors which exert their strong inhibitory effects by directly binding to the protein kinase molecules. KN-62 is a selective and potent inhibitor of Ca++/calmodulin-dependent protein kinase II (Ca++/CaM Kinase II). The inhibition of KN-62 against Ca++/CaM Kinase II is more significant than the other protein kinases and is effective in lower concentrations. KN-04, which closely resembles KN-62 in its chemical structure, exhibits a weak protein kinase inhibition and is useful as a control for KN-62. , KN-62 and KN-04 are useful tools for elucidation of the function of the enzyme in relation to cellular responses. H-89 and H-88 have a potent and selective inhibitory effect against cyclic AMP-dependent protein kinase (Protein Kinase A). , H-89 is most powerful among various protein kinase A inhibitors. H-85 closely resembles H-89 in its chemical structure. It is not specific to Protein Kinase A and has similar inhibitory effects on other kinases , hence this compound can be used as a negative control of H-89. CKI-7 has a potent inhibitory effect against casein kinase I and a much weaker effect on casein kinase II as well as other protein kinases. CKI-8, a derivative of CKI-7, is used as an affinity ligand to purify casein kinase I. These newly synthesized compounds should serve as useful tools for elucidating the biological significance of casein kinase I -mediated reactions. KN-93, a modified type of KN-62, is also a potent and specific inhibitor of Ca++/CaM Kinase II and its solubility in buffered solution is superior to KN-62. , KN-92, which closely resembles KN-93 in its chemical structure, exhibits no inhibitory effect to Ca++/CaM Kinase II and is used as a control for KN- 93. Storage and Stability: Lyophilized powder may be stored at -20°C. Stable for 6 months at -20°C. Reconstitute with DMSO for stock solution. Store at 4°C. Stock product is stable for 6 months at 4°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.