Substituted benzopyran derivatives usable against arrhythmias

摘要

This invention relates to benzopyran derivatives of the formula (1) or the formula (2) wherein R¹ and R² represent independently of each other hydrogen atom or C_1-6alkyl group, R³ represents hydroxyl group or C_1-6 alkylcarbonyloxy group, R⁴ represents hydrogen atom or C_1-6 alkyl group, R⁵ represents C_1-6 alkyl group substituted with C_6-14 aryl group or heteroaryl group, R⁶ represents C_1-6 alkyl group, C_1-6 alkoxy group, halogen atom, nitro group, C(O)NH₂, C(O)NHR⁸ or C(O)NR⁸R⁹, or pharmaceutically acceptable salts thereof. These compounds are useful as an antiarrhythmic agent