Patent ID: 8349901

Claim:
A compound of formula (I), or pharmaceutically acceptable salts thereof: wherein, a is 0; B is S—S; A is CH 2 ; A 1 is CH 2 ; D 1 represents a therapeutic agent comprising one or more of the functional groups selected from the group consisting of —OH, —SH, —NHR 1 , —CO 2 H, —CONHR 1 , —OC(═O)NHR 1 , —SO 2 NHR 1 , —OSO 2 NHR 1 , —N(R 1 )C(═O)NHR 1 and —N(R 1 )SO 2 NHR 1 ; D 2 is NO 2 ; E is CH 2 ; L 1 represents L or a linkage selected from the group consisting of: wherein: X independently represents at each occurrence a bond, O, or NR 1 ; Y independently represents at each occurrence a bond, C═O, or SO 2 ; Z represents CH 2 ; R 1 represents H or a bond to the residue of the therapeutic agent at an atom other than the atom to which N is attached; M represents Na, K or a pharmaceutically acceptable metal ion; and e is 1-3; L 2 is O; L represents a group selected from: