Compounds of the general formula Iwhereineach of m and n is independently 0 or 1；R1 and R2, together with the carbon atom to which they are attached, form a heterocyclic ring comprising one or two heteroatoms selected from oxygen, sulfur, —S(O)— and —S(O)2—；R3 is —CHF2, —CF3, —OCHF2, —OCF3, —SCHF2 or —SCF3；X is a bond, —CH2—, or —NH—；A is aryl, cycloalkyl, cycloalkenyl, arylalkyl, heteroaryl, heteroarylalkyl, heterocycloalkyl or heterocycloalkenyl, optionally substituted with one or more, same or different substituents selected from R4； andR4 is hydrogen, amino, thioxo, alkyl, haloalkyl, hydroxyalkyl, alkoxy, haloalkoxy, halogen, oxo, thia, or hydroxy；or pharmaceutically acceptable salts, hydrates or solvates thereof,have been found to exhibit PDE4 inhibiting activity, and may therefore be useful in the treatment of inflammatory diseases and disorders.
