The invention relates to thienopyrimidinediones of formula (I): ##STR00001## wherein: R.sup.1, R.sup.2, Q are as defined in the specification, and Ar and Ar.sup.2 are selected from certain aromatic ring systems which may be optionally substituted, as defined in the specification.Processes for the preparation of compounds of formula (I), pharmaceutical compositions containing them and their use in therapy are also described and claimed.