Preparation, characterization, and biological activity of amides and esters from 8-hydroxyquinoline-2-carboxylic acid and Jeffamines ED (R) or poly(ethylene glycol)s

New macromolecular chelators were synthesized under mild conditions by reac tion of 8-hydroxyquinoline-2-carboxylic acid (8Q2COOH) with polyethers havi ng amino end-groups (Jeffamines ED(R)) or poly(ethylene glycol)s in the pre sence of dicyclohexylcarbodiimide and dimethylaminopyridine. The prepared a mides (8Q2CONH-POE) and esters (8Q2COO-POE) were characterized by SEC, DSC, IR, H-1 and C-13 NMR spectroscopy, and MALDI-TOF mass spectrometry. It was found that the polyethers had 8-hydroxy-2-quinolinyl end groups and formed complexes with Fe3+ ions. The obtained complexes were studied with IR spec troscopy and DSC. The plant tests showed that the Fe3+ complex of 8Q2CONH-P OE2000 had high efficacy in the remedy of iron-deficient maize plants under hydroponic conditions.