The present invention includes compound of formula (I), ##STR00001## or a derivative thereof, wherein Y is CH or N; R.sup.1 is unsubstituted or substituted alkyl, unsubstituted or substituted cycloalkyl, unsubstituted or substituted alkenyl, unsubstituted or substituted cycloalkenyl, unsubstituted or substituted aryl, aralkyl wherein the aryl and the alkyl moieties may each independently be unsubstituted or substituted, aralkenyl wherein the aryl, and alkenyl moieties may each independently be unsubstituted or substituted, unsubstituted or substituted heterocyclyl, or heterocyclylalkyl wherein the heterocyclyl and the alkyl moieties may each independently be unsubstituted or substituted; and R.sup.2 is unsubstituted aryl or unsubstituted or substituted or substituted heteroaryl. Additionally the present invention includes a process for preparing such a compound, a pharmaceutical composition containing such a compound, and the use of such a compound in medicine.