DIBENZOFURAN DERIVATIVES AS INHIBITORS OF PDE-4 AND PDE-10

The invention relates to heterocyclic compounds useful as phosphodiesterase inhibitors (PDEs) in particular phosphodiesterase type 4 (PDE-4) and type 10 inhibitors (PDE-10) represented by formula (I), tautomeric forms, stereoisomers, diastereomers, enantiomers, appropriate N-oxides, pharmaceutically acceptable salts, pharmaceutically acceptable hydrates, pharmaceutically acceptable solvates, pharmaceutically acceptable compositions containing them and their use in treating allergic and inflammatory diseases and for inhibiting the production of Tumor Necrosis Factor (TNF-.alpha.). The compounds represented by general formula I are useful in the treatment of allergic and inflammatory diseases including asthma, COPD, allergic rhinitis, allergic conjunctivitis, respiratory distress syndrome, chronic bronchitis, nephritis, rheumatoid spondylitis, ostheoarthritis, atopic dermatitis, eosinophilic granuloma, psoriasis, rheumatoid septic shock, ulcerative colitis, parkinson's disease; multiple sclerosis, chronic inflammation, Crohn's syndrome and other inflammatory conditions of lungs, eyes, joints, bowels, skin, heart and central nervous system (CNS). The invention also relates to a process for preparing the heterocyclic compounds of the generic formula (I). L'invention concerne de nouveaux composés hétérocycliques utiles en tant qu'inhibiteurs de phosphodiestérase (PDEs), en particulier des inhibiteurs de phosphodiestérase de type 4 (PDE IV) et des inhibiteurs de phosphodiestérase de type 10 (PDE 10), des procédés servant à les préparer, des compositions pharmaceutiques les contenant et leur utilisation pour le traitement de maladies allergiques et inflammatoires, ainsi que pour inhiber la production du facteur de nécrose tumorale (TNF-.alpha.).