Sugar-metal ion interactions: The coordination behavior of cesium ion with lactose, d-arabinose and l-arabinose.

The novel cesium chloride–lactose complex (CsCl·C 12 H 22 O 10 (Cs-Lac), cesium chloride- d -arabinose and l -arabinose complexes (CsCl·C 5 H 10 O 5 , Cs-D-Ara and Cs-L-Ara) have been synthesized and characterized using X-ray diffraction, FTIR, FIR, THz and Raman spectroscopies. Cs + is 9-coordinated to two chloride ions and seven hydroxyl groups from five lactose molecules in Cs-Lac. In the structures of CsCl- d -arabinose and CsCl- l -arabinose complexes, two kinds of Cs + ions coexist in the structures. Cs1 is 10-coordinated with two chloride ions and eight hydroxyl groups from five arabinose molecule; Cs2 is 9-coordinated to three chloride ions and six hydroxyl groups from five arabinose molecules. Two coordination modes of arabinose coexist in the structures. α- d -arabinopyranose and α- l -arabinopyranose appear in the structures of Cs-D-Ara and Cs-L-Ara complexes. FTIR and Raman results indicate variations of hydrogen bonds and the conformation of the ligands after complexation. FIR and THz spectra also confirm the formation of Cs-complexes. Crystal structure, FTIR, FIR, THz and Raman spectra provide detailed information on the structure and coordination of hydroxyl groups to metal ions in the cesium chloride–lactose, cesium chloride-D- and l -arabinose complexes. [ABSTRACT FROM AUTHOR]