[Anti-inflammatory activity of aqua-bis(2,Y-diacetoxybenzoate)-copper complexes (Y=4, 5 or 6)]

In a group of binuclear copper (II) complexes of the composition [Cu2(RCOO)4(H2O)2] (R = 2,4-diacetoxyphenyl (I), 2,5-diacetoxyphenyl (II) and 2,6-diacetoxyphenyl (III)), the anti-inflammatory activity was assayed in rat paw carrageenan-induced edema. Copper (II) salicylate tetrahydrate (IV) and salicylic acid were used as standards for comparison. All compounds were applied i.p. in a single dose of 50 mumol/kg body weight, calculated for the R-COO-fragment. The Cu(II) complexes tested were clearly more effective than the corresponding free diacetoxybenzoic acids, with an exception for the 2,5-diacetoxy derivative. The average anti-inflammatory activities of copper (II) complexes were decreasing in the following order: III (71.0%) = (70.6%) > IV (57.4%) > II (18.0%). Of the acids, only 2,6-diacetoxybenzoic acid (45.2%) was effective at the level of salicylic acid (44.9%). The relationship between the coordination-chemical properties and the biological effects of the complexes tested is discussed.