Patent ID: 7893223

Claim:
A compound of general formula (I): in which: R 1 is hydrogen, C 1 -C 20 alkyl, C 3 -C 10 cycloalkyl, C 4 -C 20 cycloalkylalkyl, aryl, arylalkyl or the two R 1 groups, taken together, form a straight or cyclic C 2 -C 10 alkylene group or an ortho-disubstituted arylene; R 2 is hydrogen, carboxy, or an optionally substituted group selected from C 1 -C 20 alkyl, C 3 -C 10 cycloalkyl, C 4 -C 20 cycloalkylalkyl, aryl, arylalkyl, a group bearing an acidic moiety, and a group bearing an amino moiety, each of which may be further optionally substituted with functional groups selected from the group consisting of carboxyl, amino, aldehydes, haloalkyl, maleimidoalkyl, hydroxyl and sulfhydryl groups which allow conjugation with a suitable molecule able to interact with physiological systems; R 3 , R 4 and R 5 , which are the same or different, are hydrogen, carboxy, or an optionally substituted group selected from C 1 -C 20 alkyl, C 3 -C 10 cycloalkyl, C 4 -C 20 cycloalkylalkyl, aryl, arylalkyl, a group bearing an acidic moiety and a group bearing an amino moiety, each of which may be further optionally substituted with functional groups selected from the group consisting of carboxyl, amino, aldehydes, haloalkyl, maleimidoalkyl, hydroxyl and sulfhydryl groups which allow conjugation with a suitable molecule able to interact with physiological systems; FG, which are the same or different, are carboxy, —PO 3 H 2 or —RP(O)OH groups, wherein R is hydrogen, or an optionally substituted group selected from C 1 -C 20 alkyl, C 3 -C 10 cycloalkyl, C 4 -C 20 cycloalkylalkyl, aryl, arylalkyl, a group bearing an acidic moiety and a group bearing an amino moiety, each of which may be further optionally substituted with functional groups selected from the group consisting of carboxyl, amino, aldehydes, haloalkyl, maleimidoalkyl, hydroxyl and sulfhydryl groups which allow conjugation with a suitable molecule able to interact with physiological systems; as well as the salts thereof with physiologically compatible bases or acids.