| abstract |
Compounds of formula (I) wherein R1 and R2 are the same or different and are each optionally substituted alkyl, optionally substitued cycloalkyl, optionally subsituted aryl or optianally substituted heteroaryl groups; R3 is hydrogen or an aryl group substituent or R3 is a solid support optionally attached via a spacer; Z represents an oxygen atom, a sulphur atom or NR4; Y represents an oxygen atom, a sulphur atom or NR5; in which R4 and R5, which may be the same or different, represent hydrogen, optionally substituted alkyl containing 1 to 6 carbon atoms, optionally substituted phenyl, optionally substituted benzyl or optionally substituted .beta.-phenylethyl; and one of X1 and X2 represents a nitrogen atom and the other of X1 and X2 represents a nitrogen atom or CR6, in which R6 represents hydrogen or an aryl group substituent; are useful for the affinity binding of a prion protein. |