Patent ID: 7692012

Claim:
A compound of the formula: wherein: L-L′ is selected from the group consisting of: L′ is selected from the group consisting of CONR 5 and CONHR 6 ; or L and L′ together form the group: Wherein L″ is O, S, or NH, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are each independently selected from the group consisting of H, hydroxyl, C1-C6 alkyl optionally substituted by hydroxyl or NR 7 R 8 , C3-C6 cycloalkyl optionally substituted by hydroxyl or NR 7 R 8 , phenyl optionally substituted by C1-C3 alkyl, hydroxyl, NR 7 R 8 or SO 3 , (OCH 2 CH 2 ) n (NHCH 2 CH 2 ) n , an amino acid or a peptide consisting of 2 to 5 amino acids; R 7 and R 8 are independently H or C1-C6 alkyl, and n is an integer; or a pharmaceutically acceptable salt thereof.