The invention relates to a compound of formula (I): A-B-D-E (I) or a pharmaceutically acceptable salt, solvate or polymorph thereof, including all tautomers and stereoisomers thereof, wherein: A is selected from monocyclic and bicyclic heteroaryl, which may independently substituted by alkyl or amino； B is selected from alkyl, heteroalkyl, alkyl-amino, aryl, heteroaryl, cycloalkyl, heterocyclyl and alkylene, wherein said groups may independently be substituted by alkyl； D is selected from aryl-amino, heteroaryl-amino, cycloalkyl-amino, heterocyclyl, heterocyclyl-amino, urea, thioamide, thiourea, sulfonamide, sulfoximine and sulfamoyl, wherein said aryl, heteroaryl, cycloalkyl and heterocyclyl groups may independently be substituted； and E is selected from aryl, heteroaryl, cycloalkyl, heterocyclyl, wherein said aryl, heteroaryl, cycloalkyl and heterocyclyl groups may independently be substituted. The compounds of formula (I) are inhibitors of glutaminyl cyclase (QC, EC 2.3.2.5). QC catalyzes the intramolecular cyclization of N-terminal glutamine residues into pyroglutamic acid (5-oxo-prolyl, pGlu*) under liberation of ammonia and the intramolecular cyclization of N- terminal glutamate residues into pyroglutamic acid under liberation of water.
