Provided is a compound having at least one selected from the group consisting of cell growth promoting activity, angiogenesis promoting activity, lumen formation promoting activity, cell migration promoting activity, and neurocyte growth promoting activity, which is a chemically stable low-molecular-weight substance that has high absorbability and can be supplied stably at a low cost because of its low molecular weight. A cyclobutyl purine derivative, a tautomer or stereoisomer thereof, or a salt, solvate, or hydrate thereof according to the present invention is a cyclobutyl purine derivative represented by the following general formula (1), a tautomer or stereoisomer thereof, or a salt, solvate, or hydrate thereof.
