| 摘要 |
<p>The invention concerns a water soluble compound of formula (α) wherein: A represents naphthyl or phenyl; and Ar1 and Ar2 independently represent a saturated or aromatic carbocyclic group; Xa, Xb are independently selected among an amino group, an ammonium group and an amino group modified by a linear polyoxyalkylene chain, provided that at least one of Xa and Xb represents ammonium or modified amino.</p> |
