The present invention relates to novel compound of stemphones obtained by culturing microorganism belonging to genus Aspergillus and having ability to produce compound of stemphones selected from the group consisting of stemphone D substance, stemphone E substance, stemphone E1 substance, stemphone E2 substance, stemphone E3 substance and stemphone F substance, accumulating the compound of stemphones in the cultured mass, and isolating the compound of stemphones from the cultured mass. Since the obtained compound has enhancing activity for imipenem and activity for reducing cytotoxicity, it can be expected to be useful as lead compounds for combination remedy for methicillin resistant Staphylococcus aureus (MRSA) infection.