A Sugar Discriminating Binuclear Copper(II) Complex

Abstract

We investigated the complex formation between various underivatized carbohydrates and the binuclear copper(II) complex 1, Cu(2)(bpdpo). A combined approach of UV/vis and CD spectroscopic investigations shows a large discrimination ability of 1 for structurally closely related monosaccharides in alkaline solution. The dominating form of the binuclear copper(II) complex consists of a [Cu(2)L(-)(H)(OH)(2)](+) species between pH 11 and 13, as determined from pH-dependent spectrophotometric titration experiments. The binding strengths of the 1:1 sugar-1 complexes, derived from the biologically important monosaccharides d-mannose (3) and d-glucose (5), is about 1.5 orders of magnitude different at pH 12.40. Moreover, a blue- or a red-shift of the absorption maximum of 1 accompanies the sugar binding and highlights the ability of 1 to discriminate carbohydrates. This phenomenon is due to the number of hydroxyl groups of the particular monosaccharide involved in chelation to the binuclear metal complex.

Lanthanide complexes as fluorescent indicators for neutral sugars and cancer biomarkers

“…A main problem in the detection of neutral sugars with artificial receptors is competitive binding by bulk water. Elevated solution pH is therefore typically required to attain a useful degree of coordination and signal transduction in the most innovative new metal-based detection methods (4,5). There is an unmet demand for biomimetic sugar-sensing agents that function in neutral buffer solution (4,5).…”

Poly[(μ3-5-bromonicotinato)(5-bromonicotinato)copper(II)]

“…For related literature on paddle-wheel secondary building units, see : Chen et al (2006); Xue et al (2007); Striegler & Dittel (2003); Ma & Moulton (2007); Banerjee et al (2008); Saravanakumar et al (2004). For similar structures, see: Yakovenko et al (2009) ;Xue et al (2007).…”

“…Research interest in these compounds with copper(II) paddlewheel SBUs come from their structural diversity (Chen, et al, 2006;Xue et al, 2007) and potential applications in supramolecular medicinal chemistry (Ma & Moulton 2007), sugar discrimination (Striegler & Dittel 2003), molecular magnets (Banerjee et al, 2008;Saravanakumar et al, 2004;Yakovenko, et al, 2009), respectively. However, most…”

pH-Independent Recognition of Polyhydroxy Compounds by Niobium(V) Porphyrin Complex with Unique Sugar Selectivity

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