| abstract |
The invention provides a compound of formula (I) or a salt thereof: n n n n n n n n n n wherein:n R 1 is C 1-3 alkyl, C 1-3 fluoroalkyl, or —CH 2 CH 2 OH; R 2 is hydrogen, methyl or C 1 fluoroalkyl; R 3 is of sub-formula (aa) or (bb): nn n n n n n n n n n wherein Y is NCONH 2 and n 1 is 0 or 1;n R 4 is H; and R 5 is a group of the sub-formula (x), (y), (y1) or (z): nn n n n n n n n n n These compounds are PDE4 inhibitors. |