Pharma & Specialty Chemical Standards

Dofetilide, IUPAC name (±)-trans-4-[[2-(3,4-difluorophenyl)-1-methylethyl]amino]-2-butyrophenone, is a class III antiarrhythmic agent with molecular formula C18H22F2NO and molecular weight 307.37 g/mol. Structurally, it features a butyrophenone backbone with a 3,4-difluorophenyl group and a dimethylaminoethyl substituent. It is therapeutically used to manage atrial fibrillation and flutter. Dofetilide exhibits low water solubility, high lipophilicity, and basic pKa (8.5). Its mechanism involves selective blockade of the rapid component of the delayed rectifier potassium current (Ikr), prolonging cardiac action potential duration and QT interval.