Provided is a new anti-cancer agent lower in cell toxicity. The present invention provides the compounds represented by the general formula of "Formula 1" or the salt thereof. The compounds are compounds having an organic group introduced on a particular ketone group of VST that functions to inhibit induction of GRP 78 expression, similarly to VST, and is applicable, for example, as an anti-cancer agent. The compounds are also advantageous in that it is less toxic than VST and has lower adverse reaction. ##STR00001##