chromanol 293B

Chromanol 293B is a small molecule chromanol derivative that acts as a potent and selective blocker of the slow delayed rectifier potassium current ($I_{Ks}$), which is mediated by the $K_{v}7.1$ (KCNQ1) and KCNE1 (minK) channel complex. Originally identified by Hoechst AG (later Aventis/Sanofi) during a screen of $K_{ATP}$ channel openers, chromanol 293B was found to selectively inhibit $I_{Ks}$ without affecting other major cardiac potassium currents like $I_{Kr}$ at low concentrations, though it also weakly inhibits the CFTR chloride current. While chromanol 293B served as a key lead compound that led to the development of more potent clinical candidates like HMR 1556, it was not pursued for clinical development itself. Today, it is widely utilized as a standard pharmacological research tool to study cardiac repolarization, epithelial ion transport, and the role of KCNQ1 channels in glucose-stimulated insulin secretion.

Other names

(-)-[3R,4S]-chromanol 293B(-)-chromanol 293Bchromanol 239Bchromanol239Bchromanol-239Brel-N-[(3R,4S)-6-cyano-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-4-yl]-N-methyl-ethanesulfonamidetrans-6-cyano-4-(N-ethylsulfonyl-N-methylamino)-3-hydroxy-2,2-dimethyl-chromanetrans-N-[6-cyano-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-4-yl]-N-methyl-ethanesulfonamide