| abstract |
Disclosed is a novel compound which has a pyrazolonaphthyridine or pyrazoloquinoline skeleton, which shows an inhibitory effect on phosphodiesterase IV. In the compound, an organic group (e.g., a homocarbocyclic ring is bound to bound particularly to position 3 of a specific heterocyclic skeleton through an alkylene group, and a homocarbocyclic ring is bound particularly to position 5 of the heterocyclic skeleton. In the compound, at least one of the ring (the homocarbocyclic ring or heterocyclic ring) bound to position 3 of the pyrazolonaphthyridine skeleton and the homocarbocyclic ring bound to position 5 of the pyrazolonaphthyridine may have an alkyl halide group and/or an alkoxy halide group as a substituent. The compound or a salt thereof is useful as a phosphodiesterase IV inhibitor and shows a high inhibitory effect on phosphodiesterase IV. |