abstract |
The invention provides a compound of formula (I) or a salt thereof: formula (I) wherein: R1 is C1-3alkyl, C1-3fluoroalkyl, or -CH2CH2OH; R2 is a hydrogen atom (H), methyl or C1fluoroalkyl; R3 is of sub-formula (aa) or (bb): formulae (aa), (bb) wherein Y is NCONH2 and n1 is 0 or 1; R4 is H; and R5 is a group of the sub-formula (x), (y), (y1) or (z): formulae (x), (y), (y1), (z). The invention also relates to the use of these compounds or salts in therapy as inhibitors of phosphodiesterase type IV (PDE4). For example, it relates to their use in the treatment and/or prophylaxis of inflammatory and/or allergic diseases such as chronic obstructive pulmonary disease (COPD), asthma, rheumatoid arthritis, allergic rhinitis, psoriasis or atopic dermatitis in a mammal such as a human. |