Patent ID: 7563902

Claim:
A compound according to the formula: wherein: one of E or F represents oxygen which is linked to the ring system by a double bond, and one of F or E represents the group such that if E represents oxygen, positions 2 and 3 of the ring system are linked by a double bond, and if F represents oxygen, positions 3 and 4 of the ring system are linked by a double bond; X 1 and X 2 are independently selected from the group consisting of —O—, —S—, —NH—, and —NR—; R 1 is selected from the group consisting of alkyl, alkenyl, alkynyl, aralkyl, and alkyl, alkenyl, alkynyl, aralkyl groups that further comprise a coupling moiety, wherein said alkyl, alkenyl or alkynyl can contain up to 20 heteroatoms; R 2 and R 3 are independently selected from the group consisting of hydrogen, R, halogen, —NR 2 , —OR, —OH, —S(O) 2 OH, —CN, —SCN, —SSR, —SR, —C(O)R, —C(O)H, —C(O)OR, —C(O)OH, —NHC(O)R, —C(O)NHR, —C(O)NH 2 , —S(O) 2 NHR, and —S(O) 2 NH 2 , or R 2 and R 3 together with the atoms to which they are bound form part of a fused aryl ring; R 4 is selected from the group consisting of hydrogen, R, halogen, —NR 2 , —OR, —OH, —S(O) 2 OH, —CN, —SCN, —SSR, —SR, —C(O)R, —C(O)H, —C(O)OR, —C(O)OH, —NHC(O)R, —C(O)NHR, —C(O)NH 2 , —S(O) 2 NHR and —S(O) 2 NH 2 ; R 5 and R 7 are independently selected from the group consisting of hydrogen, R, halogen, —NR 2 , —OR, —OH, —S(O) 2 OH, —CN, —SCN, —SSR, —SR, —C(O)R, —C(O)H, —C(O)OR, —C(O)OH, —NHC(O)R, —C(O)NHR, —C(O)NH 2 , —S(O) 2 NHR, and —S(O) 2 NH 2 , or R 5 and R 8 , or R 7 and R 9 , or R 5 and R 8 , and R 7 and R 9 together with the atoms to which they are bound form part of a fused aryl ring; R 6 is selected from the group consisting of —OH, —OR 8 , —NH 2 , —NHR 8 , and —NR 8 , R 9 ; wherein R 8 is selected from the group consisting of alkyl, alkenyl, alkynyl and aralkyl, wherein said alkyl, alkenyl or alkynyl can contain up to 20 heteroatoms, or R 8 and R 5 together with the atoms to which they are bound form part of a fused aryl ring; R 9 is selected from the group consisting of alkyl, alkenyl, alkynyl, and aralkyl, wherein said alkyl alkenyl or alkynyl can contain up to 20 heteroatoms, or R 9 and R 7 together with the atoms to which they are bound form part of a fused aryl ring; R is selected from the group consisting of alkyl, alkenyl, alkynyl, and aralkyl wherein said alkyl, alkenyl, or alkynyl can contain up to 20 heteroatoms; Z comprises a leaving group; and A comprises a counter-ion to balance a net charge of the compound.