| abstract |
The present invention provides compounds of formula I: [Wherein, X, A, G, E, R 1 , R 2 , R 3 are as defined in the specification] And a pharmaceutically acceptable salt, hydrate, N-oxide or solvate thereof. The compounds are used as phosphodiesterase inhibitors, in particular as PDE4 inhibitors. The present invention also relates to the compound used in medicine, a pharmaceutical composition containing the compound, a method for treating a disease (for example, skin disease) using the compound, and the use of the compound in the manufacture of a medicament. |