To provide a compound having a strong intraocular pressure lowering effect and having no eye side effects such as eye irritation and aqueous humor protein increase. The compound represented by the general formula (I) (wherein the definitions of each group are as described in the specification), a salt thereof, a solvate thereof, or a prodrug thereof has a strong intraocular pressure lowering action. Furthermore, since there are no side effects on the eye such as eye irritation (hyperemia, corneal turbidity, etc.) and aqueous humor protein elevation, it can be a highly safe and excellent preventive and / or therapeutic agent for glaucoma.眼圧下降作用が強く、眼刺激性、房水タンパク質上昇等の眼に対する副作用のない化合物を提供すること。一般式（Ｉ）（式中、各基の定義は明細書中の記載の通り。）で示される化合物、その塩またはその溶媒和物、またはそのプロドラッグは、強い眼圧下降作用を有し、さらに、眼刺激性（充血、角膜混濁等）、房水タンパク質上昇等の眼に対する副作用がないことから、安全性が高く、かつ優れた緑内障等の予防および／または治療剤となりうる。
