Tetrahydrothiopy ranphthalazinone derivatives as PDE4 inhibitors

Compounds of formula I

• 15
• in which
• R1 and R2 are both hydrogen or together form an additional bond,
• A represents S (sulfur), S(O) (sulfoxide) or S(O)2 (sulfone),
• Ar represents a benzene derivative of formula (a) or (b)
• 16
• wherein
• R3 is halogen, 1-4C-alkoxy, or 1-4C-alkoxy which is completely or predominantly substituted by fluorine,
• R4 is halogen, 1-8C-alkoxy, 3-7C-cycloalkoxy, 3-7C-cycloalkylmethoxy, or 1-4C-alkoxy which is completely or predominantly substituted by fluorine,
• R5 is halogen, 1-4C-alkoxy, 3-5C-cycloalkoxy, 3-5C-cycloalkylmethoxy, or 1-4C-alkoxy which is completely or predominantly substituted by fluorine,
• R6 is 1-4C-alkyl and
• R7 is hydrogen or 1-4C-alkyl,
• or wherein
• R6 and R7 together and with inclusion of the two carbon atoms, to which they are bonded, form a spiro-linked 5-, 6- or 7-membered hydrocarbon ring, optionally interrupted by an oxygen or sulphur atom,
• and the salts of these compounds, with the proviso, that those compounds of formula I are excluded, in which A represents S (sulfur) and Ar represents a benzene derivative of formula (a) and both of R3 and R4 are other than halogen.