PROBLEM TO BE SOLVED: To provide, from a novel natural product skeleton, a Ngn2 promoter activator for which there is a high possibility to bring about the differentiation of a neural stem cell.SOLUTION: The Ngn2 promoter activator comprises at least one of the following (1) and its derivative, and salt thereof.【課題】神経幹細胞の分化につながる可能性の高いNgn2プロモーター活性剤を新規天然物骨格から提供する。【解決手段】下記(1)及びそれらの誘導体並びにその塩の少なくともいずれかを含むことを特徴とする。【選択図】図1