The present invention relates to a compound represented by the formula (I-al -a),(see formula I-a1-a)a salt thereof or a solvate thereof, which has a leukotriene receptorantagonistic activity which isexpected to be more effective than those of the leukotriene receptorantagonists currently used in clinical trials.Therefore, it is useful as an agent for the prevention and/or treatment of aleukotriene-mediated disease such as arespiratory diseases such as bronchial asthma, chronic obstructive pulmonarydisease, pulmonary emphysema,chronic bronchitis, pneumonia (e.g. interstitial pneumonia etc.), severe acuterespiratory syndrome (SARS), acuterespiratory distress syndrome (ARDS), allergic rhinitis, sinusitis (e.g acutesinusitis, chronic sinusitis, etc.), or thelike, or as an expectorant or an antitussive.
