Novel carbohydrate-appended metal complexes for potential use in molecular imaging.
Seven discrete sugar-pendant diamines were complexed to the {M(CO)(3)}(+) ((99m)Tc/Re) core: 1,3-diamino-2-propyl beta-D-glucopyranoside (L(1)), 1,3-diamino-2-propyl beta-D-xylopyranoside (L(2)), 1,3-diamino-2-propyl alpha-D-mannopyranoside (L(3)), 1,3-diamino-2-propyl alpha-D-galactopyranoside (L(4)), 1,3-diamino-2-propyl beta-D-galactopyranoside (L(5)), 1,3-diamino-2-propyl beta-(alpha-D-glucopyranosyl-(1,4)-D-glucopyranoside) (L(6)), and bis(aminomethyl)bis[(beta-D-glucopyranosyloxy)methyl]methane (L(7)). The Re complexes [Re(L(1)-L(7))(Br)(CO)(3)] were characterized by (1)H and (13)C 1D/2D NMR spectroscopy which confirmed the pendant nature of the carbohydrate moieties in solution. Additional characterization was provided by IR spectroscopy, elemental analysis, and mass spectrometry. Two analogues, [Re(L(2))(CO)(3)Br] and [Re(L(3))(CO)(3)Br], were characterized in the solid state by X-ray crystallography and represent the first reported structures of Re organometallic carbohydrate compounds. Conductivity measurements in H(2)O established that the complexes exist as [Re(L(1)-L(7))(H(2)O)(CO)(3)]Br in aqueous conditions. Radiolabelling of L(1)-L(7) with [(99m)Tc(H(2)O)(3)(CO)(3)](+) afforded in high yield compounds of identical character to the Re analogues. The radiolabelled compounds were determined to exhibit high in vitro stability towards ligand exchange in the presence of an excess of either cysteine or histidine over a 24 h period.
Storr
Tim
T
Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada.
Obata
Makoto
M
Fisher
Cara L
CL
Bayly
Simon R
SR
Green
David E
DE
Brudziñska
Izabela
I
Mikata
Yuji
Y
Patrick
Brian O
BO
Adam
Michael J
MJ
Yano
Shigenobu
S
Orvig
Chris
C
D002241:Carbohydrates / Q000737:chemistry*; D003847:Deoxyglucose / Q000737:chemistry; D019788:Fluorodeoxyglucose F18; D008958:Models, Molecular; D008968:Molecular Conformation; D009005:Monosaccharides / Q000737:chemistry*; D019275:Radiopharmaceuticals; D012211:Rhenium; D013667:Technetium
D002241:Carbohydrates; D009005:Monosaccharides; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D012211:Rhenium; D013667:Technetium; D003847:Deoxyglucose