The present invention relates to novel heterocyclic compounds that are
useful as phosphodiesterase inhibitors (PDEs) in particular
phosphodiesterase type 4 (PDE IV) inhibitors and phosphodiesterase type
10 (PDE 10) inhibitors, processes for their preparation, pharmaceutical
compositions containing them and their use in treating allergic and
inflammatory diseases as well as for inhibiting the production of Tumor
Necrosis Factor (TNF-.alpha.).
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