A compound represented by general formula (I) (wherein all symbols are as defined in the description) or a salt, solvate, N-oxide form or prodrug thereof is a potent FXIa inhibitor, has excellent oral absorption properties and kinetics in blood, can exert a potent anti-coagulation activity over a long period of time after being administered orally, and has a discrepancy between the anti-coagulation activity thereof and the CYP-inhibiting activity thereof. Therefore, the compound or the salt, solvate, N-oxide form or prodrug thereof can be used as an efficient prophylactic and/or therapeutic agent for vascular occlusive diseases.
