Complexes of carbohydrates with metal cations. III. Conformations of alditols in aqueous solution

Abstract

Complex formation of alditols with metal ions in aqueous solution has been investigated by electrophoresis and by the study of the n.m.r. spectra in the presence of europium ions. Complexing occurs at three consecutive oxygen atoms which are in a gauche-gauche arrangement; the energy required to form this arrangement (by rotation around carbon-carbon bonds) determines the extent of complex formation. It appears that the alditols in aqueous solution are essentially in the same conformations as are their acetates in chloroform solution.

A 500-MHz Proton-Magnetic-Resonance Study of Several Fragments of the Carbohydrate-Protein Linkage Region Commonly Occurring in Proteoglycans

“…At 500 MHz, the spectrum of Xyl-01, a symmetric alditol, is nearly first-order, enabling straightforward interpretation without use of complexing agents of shift reagents (cf. [21,22]). …”

Use of Polyols in Oral Biology Research

“…Recently, these contentions received support in a study by Sato et al (2011): bone density increased in the femurs of rats receiving 10% and 20% xylitol in their diet. These results should be contemplated against the ability of xylitol to complex with Ca(II), as discussed in several connections (Angyal et al, 1974;Mäkinen, 2000Mäkinen, , 2010. Finally the potential of erythritol as a safe and efficacious sugar substitute in oral biologic applications must be emphasized.…”

“…The structures shown include some alditols whose oral biologic effects have not been studied but which, based on their detailed chemical configuration, warrant future investigation as potential chemical effectors of dental plaque. Several text books and research papers have elucidated the chemistry and physiology of alditols in detail (Carr & Krantz, 1945;Lohmar, 1962;Touster & Shaw, 1962;Mills, 1974;Angyal et al, 1974;Gekko & Satake, 1981;Georgieff et al, 1985;Mäkinen, 2000Mäkinen, , 2010Mäkinen, , 2011. There is an ever-growing body of research describing the medical, pharmaceutical, nutritional, technical, cosmetic, and other applications of alditols.…”

Topics in carbohydrate stereochemistry

“…The preponderant conformation of alditols with a yj sequence is a sickle form (see above) which has to change into the planar zigzag in order to form a complex with the cation (ref. 16). Apparently the tripositive La(III) ion has greater propensity to induce this change than the dipositive Ca(II) ion.…”