[Problem] Provided is a non-peptide compound which can be used as a GAPDH aggregation inhibitor. [Solution] Provided is a GAPDH aggregation inhibitor including as an active ingredient a compound represented by the chemical formula 1 wherein R 1 , R 2 , and R 3 are each independently a hydrogen atom, a halogen atom, or an aliphatic hydrocarbon group having a carbon number of from 1 to 10, a polysulfurized derivative thereof, or a pharmaceutically acceptable salt thereof. The present compound has a GAPDH aggregation inhibitory activity to suppress intracerebral aggregation of various proteins involved in cerebral neurodegenerative diseases, thereby contributing to improvement in various brain neurological diseases associated with aggregation of these proteins such as Alzheimer's disease, Parkinson's disease, and cerebral infarction, and prevention of advanced seriousness of these diseases.