Provision of orally-available and low-toxic somatostatin receptor subtype 2 agonist. Since the compound represented by the general formula (I) : wherein all symbols represent the same meanings as those described in the description, a salt thereof, an N-oxide thereof, a solvate thereof, or a prodrug thereof is non-peptidic low-molecular compound which has strong somatostatin receptor subtype 2 agonist activity, the compound is orally-available. Additionally, since the compound is low-toxic, the compound is useful for the prevention and/or treatment of the somatostatin related diseases such as acromegaly or gastrointestinal obstruction.