Structures of the Fe chelators examined in this study.

(A) General structure of the 2-hydroxy-1-naphthylaldehyde thiosemicarbazone (NT) analogues along with their numbering scheme. (B) Desferrioxamine (DFO), 2-hydroxy-1-naphthylaldehyde isonicotinoyl hydrazone (311), 2-hydroxy-1-naphthylaldehyde nicotinoyl hydrazone (311m), salicylaldehyde thiosemicarbazone (ST), 2-hydroxy-1-naphthylaldehyde thiosemicarbazone (NT), 2-hydroxy-1-naphthylaldehyde-2-methyl-3-thiosemicarbazone (N2mT), 2-hydroxy-1-naphthylaldehyde-4-methyl-3-thiosemicarbazone (N4mT), 2-hydroxy-1-naphthylaldehyde-4,4-dimethyl-3-thiosemicarbazone (N44mT), 2-hydroxy-1-naphthylaldehyde-4-ethyl-3-thiosemicarbazone (N4eT), 2-hydroxy-1-naphthylaldehyde-4-allyl-3-thiosemicarbazone (N4aT), 2-hydroxy-1-naphthylaldehyde-4-phenyl-3-thiosemicarbazone (N4pT), 2-hydroxy-1-naphthylaldehyde-4,4-diphenylhydrazone (N44pH), and 2-hydroxy-1-naphthylaldehyde-4-octylhydrazone (NoctH).