The present invention provides compounds of Formula (I) as inhibitors of LMP7 for the treatment of autoimmune and inflammatory diseases. In formula (I), Rb and Rc are independently selected from one another from H or C1-C6-alkyl whereby Rb and Rc may be linked to form a 5 or 6 membered-ring containing the oxygen atoms to which they are linked Q denotes Ar, Het or cycloalkyl R1 R2 independently from each other denotes H, ORa, Hal, C1-C6-alkyl wherein 1 to 5 H atoms may be independently replaced by OH or Hal Y denotes CR 3R4, preferably CH2 or C(CH3)2 R 3, R4 independently of one another denote H or C1-C6-alkyl L denotes L1 or L2 or alkyl n is an integer selected from 0 to 3 L 1 is Q1-CO-M- wherein Q 1 is Ar or Het, preferably, phenyl, naphthyl or pyridine, optionally substituted with 1 to 5 groups independently selected from ORa, Hal, phenyl, and C1-C6-alkyl wherein 1 to 5 H atoms may be independently replaced by OH or Hal L2 is Q2-M- wherein Q 2 is a fused bicyclic system containing 1 nitrogen atom and 1 to 3 additional groups independently selected from O, S, N, or CO, and wherein at least one of the rings is aromatic whereby the fused bicyclic system is optionally substituted with 1 to 5 groups independently selected from ORa, Hal, phenyl, and C1-C6-alkyl wherein 1 to 5 H atoms may be independently replaced by OH or Hal or Q 2 is unsaturated or aromatic 5 membered-ring system containing 1 to 3 heteroatoms selected from N, O, S and CO, and optionally substituted with a phenyl ring or pyridine ring whereby phenyl ring and pyridine ring are optionally substituted with 1 to 4 groups independently selected from ORa, Hal, phenyl, and C1-C6-alkyl wherein 1 to 5 H atoms may be independently replaced by OH or Hal M is a linear or branched alkylene having 1 to 5 carbon atoms wherein 1 or 2 H atoms may be replaced by OR a or a phenyl ring optionally substituted with 1 to 5 groups independently selected from Hal, ORa, and C1-C6-alkyl optionally substituted with 1 to 5 groups
