The purpose of the present invention is to provide a novel trans 2 decenoic acid derivative and a pharmaceutically acceptable salt thereof and a medicament containing the compound described above as an active component and having a neurotrophic factor like effect and a side effect reducing effect due to administration of anti cancer agent which are highly safe. A trans 2 decenoic acid derivative or the pharmaceutically acceptable salt thereof which is a compound of the present invention is specifically represented by general formula (1) (where Y represents -O-,-NR-,or -S-,R represents a hydrogen atom, an alkyl group, a dialkylamino group, or the like, and W represents a substituent such as a dialkylaminoalkyl group) and is extremely highly useful as a preventive or therapeutic agent for dementia, Alzheimer"s disease, Parkinson s disease, depression and the like, a therapeutic or repairing agent for spinal cord injury, or a medicament such as an agent for reducing the side effect due to administration of anti-cancer agent.
