The synthesis, characterization, antimicrobial and antimutagenic activities of hydroxyphenylimino ligands and their metal complexes of usnic acid isolated from Usnea longissima.

Novel multifunctional hydroxyphenylimino ligands (L1, L2 and L3) were synthesized by the condensation of 2-aminophenol, 3-aminophenol and 4-aminophenol with usnic acid, a lichen metabolite. The synthesized ligands and their Cu(II), Co(II), Ni(II) and Mn(II) complexes were characterized using FT-IR, UV-Vis, (1)H-NMR, (13)C-NMR, 1D- and 2D NMR (DEPT, COSY, HMQC and HMBC), LC-MS and TGA. In addition, the metal complexes of the novel ligands were prepared with high yields using Cu(II), Co(II), Ni(II) and Mn(II) salts and were characterized using the FT-MIR/FAR, UV-Vis, elemental analysis, ICP-OES and TG/DTA techniques.