Discrimination of cis-trans isomers by dinuclear metal cryptates at physiological pH: selectivity for fumarate vs. maleate.

Dalton transactions (Cambridge, England : 2003)

PubMedID: 23912154

Xie GY, Jiang L, Lu TB. Discrimination of cis-trans isomers by dinuclear metal cryptates at physiological pH: selectivity for fumarate vs. maleate. Dalton Trans. 2013;.
Cryptand ( = N[(CH2)2NHCH2(2,6-C10H6)CH2NH(CH2)2]3N) and its dinuclear metal cryptates [Zn2L](NO3)4 () and [Cu2L](ClO4)4 () have been prepared, and the binding properties of the cryptates with fumarate and its cis isomer maleate were investigated using fluorescent spectra, (1)H NMR titrations and single crystal X-ray diffraction analysis for [(Cu2L)(fum)][ClO4]2 () (fum = fumarate). Thanks to the size and shape matching effect, the cryptates can selectively recognize fumarate at physiological pH, with an association constant almost 18-fold larger than that of maleate, forming a cradle-like cascade complex.