Abstract: A compound of formula (I): ##STR1## or a tautomeric form thereof and/or a pharmaceutically acceptable salt thereof, and/or a pharmaceutically acceptable solvate thereof, wherein:A.sup.1 represents a substituted or unsubstituted aryl group;A.sup.2 represents a benzene ring having in total up to five substituents;X represents O, S or NR.sup.1 wherein R.sup.1 represents a hydrogen atom, an alkyl group, an acyl group, an aralkyl group, wherein the aryl moiety may be substituted or unsubstituted, or a substituted or unsubstituted aryl group;Y represents O or S;R.sup.2 represents hydrogen;R.sup.3 represents hydrogen or an alkyl, aralkyl or aryl group or R.sup.2 together with R.sup.3 represents a bond; andn represents an integer in the range of from 2 to 6; a process for preparing such a compound, a pharmaceutical composition comprising such a compound and the use of such compound and composition in medicine.

Abstract: A compound of formula (I): ##STR1## or a tautomeric form thereof and/or a pharamaceutically acceptable salt thereof, and/or a pharmaceutically acceptable solvate thereof, wherein:A.sup.1 represents a substituted or unsubstituted aromatic heterocyclyl group;A.sup.2 represents a benzene ring having in total up to five substituents;X represents O, S or NR.sup.1 l wherein R.sup.1 represents a hydrogen atom, an alkyl group, an acyl group, an aralkyl group, wherein the aryl moiety may be substituted or unsubstituted, or a substituted or unsubstituted aryl group;Y represents O or S providing that Y does not represent O when X represents NR.sup.1 ;R.sup.2 and R.sup.3 each represent hydrogen, or R.sup.2 and R.sup.3 together represent a bond; andn represents an integer in the range of from 2 to 6; a process for preparing such a compound; a pharmaceutical composition comprising such a compound; and the use of such a compound and a composition in medicine.