Patent ID: 7026350

Claim:
A water-soluble compound of the formula or a pharmaceutically acceptable salt thereof, wherein: R 1 is a charged aliphatic moiety at neutral pH, which optionally is substituted by an aryl ring, wherein said aliphatic moiety is substituted by one or more charged moieties, which can be the same or different, selected from the group consisting of carbamate, carbonate, phosphamate, phosphate, phosphonate, pyrophosphate, triphosphate, sulfamate, sulfate, a C 1 –C 8 monoalkylamine that is protonated at neutral pH, a C 1 –C 4 dialkylamine that is protonated at neutral pH, and a C 1 –C 4 trialkylammonium, R 2 is a halo or an —OR 8 when there is a single bond between R 2 and the carbon at position 11, wherein R 8 is selected from the group consisting of hydrogen, a C 1 –C 8 alkylamido, a C 1 –C 8 alkyl, a C 2 –C 8 alkenyl, a C 2 –C 8 alkynyl, a C 1 –C 8 hydroxyalkyl, a C 1 –C 8 alkyl carbamoyl, a C 1 –C 8 alkylcarbonyl, and an aralkyl, any of which R 8 groups can be further substituted with one or more substituents, which can be the same or different, selected from the group consisting of nitro, halo, azido, hydroxy, amido and amino, or R 2 is oxo (═O) or oximino (═NOH) when there is a double bond between R 2 and the carbon at position 11, R 3 is selected from the group consisting of hydrogen and a group of the formula wherein R 5, R 6, and R 7 are each independently selected from the group consisting of hydrogen, a halo, an azido, a nitro, a C 1 –C 8 alkyl, a C 1 –C 8 alkoxy, an aryl, a cyano, and an NR 10 R 11 R 12, wherein R 10, R 11, and R 12 are each independently selected from the group consisting of hydrogen and a C 1 –C 3 alkyl, R 4 is selected from the group consisting of hydrogen, a halo, a C 1 –C 8 alkylamino, and a C 1 –C 8 dialkylamino, and the bond between the carbons at positions 4 and 5 can be a single bond or a double bond.