The present invention relates to benzopyran derivatives substituted with a thioxobenzoxazole derivative, or pharmaceutically acceptable salts thereof, processes for preparing the same and a pharmaceutical composition containing the above as an effective ingredient Benzopyran derivatives substituted with thioxobenzoxazole derivatives, represented in , have the function of protecting heart from ischemia-reperfusion both in vivo and in vitro, so that a pharmaceutical composition containing benzopyran derivatives substituted with thioxobenzoxoazole derivatives or pharmaceutically acceptable salts thereof of the present invention as an effective ingredient can be effectively used for the protection of tissues influenced by ischemia-reperfusion, for example, for the protection of heart, nervous cells, brain, retinal cells, storage organs, etc, and for the treatment of diseases caused by ischemia-reperfusion.