Patent ID: 7276494

Claim:
A compound comprising a photosensitising chromophoric system (Phot), a sulphonamido functionality and a carboxy functionality or a pharmaceutically acceptable salt thereof, in which the Phot is selected from a residue of a metal-free phthalocyanine, a metal phthalocyanine, a benzoporphyrin, a purpurin, a chlorin, a bacteriochlorin, a tetraarylporphyrin, a porphycene and a texaphyrin, wherein: the metal phthalocyanine carries from 1 to 8 substituents selected from —SO 2 NY—X—CO 2 H and —Z—SO 2 NY—X—CO 2 H, and the chlorin, bacteriochlorin and tetraarylporphyrin carry from 1 to 4 substituents selected from —SO 2 NY—X—CO 2 H and —Z—SO 2 NY—X—CO 2 H, in which X is a linear or branched alkyl or alkenyl group having from 0 to 5 carbon atoms which arts optionally substituted by at least one of hydroxyl, methoxy, ethoxy, fluoro, chloro, carboxymethyl or carboxyamide; Y is hydrogen or a an linear or branched alkyl having from 1 to 5 carbon atoms which are optionally substituted by at least one hydroxy; and Z is a linking group; excluding the compounds tetrasulphonylaminoglycine zinc (II) phthalocyanine, tetrasulphonylamino β-alanine zinc (II) phthalocyanine, tetrasulphonylamino-α-alanine zinc (II) phthalocyanine, tetrasulphonylamino butyric acid zinc (II) phthalocyanine, tetrasulphonylamino valeric acid zinc (II) phthalocyanine, and tetrasulphonylamino caproic acid zinc (II) phthalocyanine.