IT IS INTENDED TO PROVIDE A BICYCLIC Y-AMINO ACID DERIVATIVE HAVING EXCELLENT ACTIVITY AS AN α2δ LIGAND. THE PRESENT INVENTION PROVIDES A COMPOUND REPRESENTED BY THE GENERAL FORMULA (I): WHEREIN R1,R2,R2’,R4,R5,R6,R7,R8,AND R8’ ARE A HYDROGEN ATOM OR THE LIKE; AND R3 IS A HYDROGEN ATOM, A HALOGEN ATOM,A C1-C6 ALKYL GROUP, OR THE LIKE.