Patent ID: 8357210

Claim:
A compound of the general formula (I) wherein R 1 , R 2 , R 9 and R 10 are independently selected from the group consisting of: unsubstituted unbranched C 1-6 alkyl, unsubstituted branched C 3-6 alkyl, substituted unbranched C 1-6 alkyl, substituted branched C 3-6 alkyl, aryl, and —(CH 2 ) p -aryl wherein p=1, 2, 3 or 4, R 3 and R 8 is selected from the group consisting of: hydrogen, unsubstituted unbranched C 1-6 alkyl, unsubstituted branched C 3-6 alkyl, substituted unbranched C 1-6 alkyl, substituted branched C 3-6 alkyl, unsubstituted unbranched C 1-6 alkoxy, unsubstituted branched C 3-6 alkoxy, substituted unbranched C 1-6 alkoxy, substituted branched C 3-6 alkoxy, halogen, —NHCO—(C 1-6 alkyl) with an unbranched C 1-6 alkyl group, which is substituted or unsubstituted, —NHCO—(C 3-6 alkyl) with a branched C 3-6 alkyl group, which is substituted or unsubstituted, and —NHCONH 2 , BR is a bridge of the formula -A-B-A- wherein A is selected from the group consisting of: substituted phenyl, substituted naphthyl, unsubstituted phenyl, and unsubstituted naphthyl, and B is a bridging sulphon, the compound of the formula (I) contains 1, 2 or 3 sulpho groups and wherein there are no anionic groups in the bridging member BR.