The present invention provides a somatostatin receptor subtype 2 agonist. A disclosed compound represented by the general formula (I): wherein all symbols have the same definitions as described in the specification; a salt thereof, an N-oxide thereof or a solvate thereof, or a prodrug of the foregoing is a low-molecular compound having strong somatostatin receptor subtype 2 agonistic activity, and thus can be administered in a simple manner, has high stability and has low toxicity. Therefore, the present compound is useful for prophylaxis and/or therapy of somatostatin-related diseases such as acromegaly and gastrointestinal obstruction.