| Abstract
| - This work describes the use of 3-hydroxy-4-pyridinone ligands for binding the [M(CO)3]+ core (M = Re, Tc) inthe context of preparing novel Tc(I) and Re(I) glucose conjugates. Five pyridinone ligands bearing pendentcarbohydrate moieties, HL1-5, were coordinated to the [M(CO)3]+ core on the macroscopic scale (M = Re) andon the tracer scale (M = 99mTc, 186Re). On the macroscopic scale the complexes, ReL1-5(CO)3(H2O), werethoroughly characterized by mass spectrometry, IR spectroscopy, UV−visible spectroscopy, elemental analysis,and 1D/2D NMR spectroscopy. Characterization confirmed the bidentate coordination of the pyridinone and thependent nature of the carbohydrate and suggests the presence of a water molecule in the sixth coordination site.In preliminary biological evaluation, both the ligands and complexes were assessed as potential substrates orinhibitors of hexokinase, but showed no activity. Labeling via the [99mTc(CO)3(H2O)3]+ precursor gave the tracerspecies 99mTcL1-5(CO)3(H2O) in high radiochemical yields. Similar high radiochemical yields when labelingwith 186Re were facilitated by in situ preparation of the [186Re(CO)3(H2O)3]+ species in the presence of HL1-5 togive 186ReL1-5(CO)3(H2O). Stability challenges, incubating 99mTcL1-5(CO)3(H2O) in the presence of excess cysteineand histidine, confirmed complex stability up to 24 h.
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