PROBLEM TO BE SOLVED: To provide a curative medicine and/or a preventive medicine for respiratory diseases such as asthma and chronic obstructive pulmonary disease.SOLUTION: A new pyridylaminoacetic acid compound, which has an EP2 agonist action and is shown by general formula (1) (in which Rto Rare each a hydrogen atom, a 1-6C alkyl group or the like independently; Y is a halogen atom, a 1-6C alkyl group or the like; Z is a halogen atom, an aromatic ring group optionally-replaced by a halogen atom, a 1-6C alkyl group or the like, or 5-membered or 6-membered heteroaromatic ring group), or the pharmacologically acceptable salt thereof is provided.【課題】喘息や慢性閉塞性肺疾患などの呼吸器疾患に対する治療薬及び/又は予防薬の提供。【解決手段】EP2アゴニスト作用を有する一般式(1)で表される新規ピリジルアミノ酢酸化合物又はその薬理上許容される塩の提供。[R1~R3は各々独立して水素原子又はC1-C6アルキル基等;Yはハロゲン原子、C1-C6アルキル基等;Zはハロゲン原子、C1-C6アルキル基等から選択される基で置換されていてもよい芳香環基若しくは5乃至6員環複素芳香環基]【選択図】なし