Abstrakt
This study tested the interaction of a series of natural coumarins and their synthetic analogs with copper. Both competitive and non-competitive methods have been employed.
Non-competitive studies showed that cuprous ions are not chelated at all and that the stoichiometries of the most active 6,7- and 7,8-dihydroxycoumarins to cupric ions ranged from 1:1 to 2:1 depending on pH and concentration. Interestingly, under highly competitive conditions, coumarins were not capable of chelating cupric ions, either.
Reduction experiments have shown that 13 out of the 15 coumarins included in this study reduced cupric ions. However, significant differences depending on their structures were apparent in their potencies.
O-dihydroxycoumarins were the most potent ones again.