CA2285264A1 — Condensed pyridazine derivatives, their production and use

USPTO Abstract

The present invention provides a compound represented by formula (I) wherein Ar1 and Ar2 are independently an aromatic group which may be substituted, and Ar1 and Ar2 may form a condensed cyclic group with an adjacent carbon atom; ring B is a nitrogen-containing heterocycle which may be substituted; X and Y are the same or different and are independently a bond, an oxygen atom, S(O)p (p is an integer of 0 to 2), NR4 wherein R4 is a hydrogen atom or a lower alkyl group, or a bivalent linear lower haydrocarbon group which may contain 1 to 3 hetero atoms and the bivalent linear lower hydrocarbon group may be substituted; A is a nitrogen atom or CR7 wherein R7 is a hydrogen atom, a halogen atom, a hydrocarbon which may be substituted, an acyl group or a hydroxy group which may be substituted; R1, R2 and R3 are the same or different and are independently a hydrogen atom, a halogen atom, a hydrocarbon group which may be substituted, an acyl group or a hydroxy group which may be substituted; R8 is a hydrogen atom, a hydroxy group which may be substituted by a lower alkyl or a carboxyl group, or a salt thereof, which exhibits excellent antihistaminic or eosinophil chemotaxis-inhibiting activities and is useful in treatment or prevention of asthma, allergic conjunctivitis, allergic rhinitis, chronic urticaria or atopic dermatitis.