Abstract A series of new long-chain arylpiperazine (LCAP) derivatives with flexible and partly constrained alkyl linker were synthesized and investigated in vitro as potential serotonin 5-HT 1A and 5-HT 7 receptor ligands. The compounds were prepared by a two- step procedure using naphthalimide and 2H-1, 3-benzoxazine-2, 4 (3H)-dione as imides, and 1-(2-methoxyphenyl) piperazine (o-OMe-PhP) and 1, 2, 3, 4-tetrahydroisoquinoline ( ...