Imidazopyrimidine derivatives and triazolopyrimidine derivatives

A compound of the formula (I) ##STR1##

in which R¹ is -OR¹¹, -SR¹¹, -SOR¹¹, -SO₂R¹¹, -NHR¹¹, or -NR¹²R¹³ , and R¹¹, R¹², and R¹³ are as defined broadly in the text. R² is H, C₁-C₆alkyl, carbamoyl, or an ester group. R³ is thienyl, pyridyl optionally substituted by halogen or C₁-C₆alkoxy; naphthyl optionally substituted by C₁-C₆alkoxy; dioxane fused phenyl; dioxacyclopentane fused phenyl; or optionally substituted phenyl. Y is CH or N. A process for preparing such compounds, pharmaceutical compositions containing such compounds, and a method of treating asthma using them are also disclosed and claimed.