Disclosed are compounds of formula (I) ##STR00001## Where Ar.sub.1, X,
R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are defined herein. The compounds
of the invention inhibit production of cytokines and are thus useful for
treating cytokine mediated diseases. Also disclosed are processes for
preparing these compounds and pharmaceutical compositions comprising
these compounds.