Dependence of Pyranose Ring Puckering on Anomeric Configuration: Methyl Idopyranosides

Dependence of pyranose ring puckering on anomeric configuration: methyl idopyranosides.

In the aldohexopyranose idose, the unique presence of three axial ring hydroxyl groups causes considerable conformational flexibility, rendering it challenging to study experimentally and an excellent model for rationalizing the relationship between puckering and anomeric configuration. Puckering in methyl α- and β-L-idopyranosides was predicted from kinetically rigorous 10 μs simulations using...

ribose ring puckering

Another method for specifying furanose ring puckering.

A set of pseudorotation coordinates is proposed for characterizing the puckering of the furanose ring. These are defined from the curvilinear displacements of the C1' and C4' atoms from the planar conformation. The present coordinates have some practical advantages over the ones currently used.

Atomic levers control pyranose ring conformations.

Atomic force microscope manipulations of single polysaccharide molecules have recently expanded conformational chemistry to include force-driven transitions between the chair and boat conformers of the pyranose ring structure. We now expand these observations to include chair inversion, a common phenomenon in the conformational chemistry of six-membered ring molecules. We demonstrate that by st...

Crystal Structure of Methyl 4-amino-4-cyano-4,6-dideoxy-2,3- O-isopropylidene-α-L-talopyranoside

The structure of methyl 4-amino-4-cyano-4,6-dideoxy-2,3-O-isopropylidene-α-Ltalopyranoside was established by X-ray analysis confirming a talo configuration at C-4 and suggesting a C4 conformation of the pyranose ring. The values of relevant torsion angles and calculated puckering parameters revealed a distortion into the direction of E conformation, thus indicating a flattening at C-2.