A theoretical study of the conformational behavior of analogues of alpha-L-rhamnose-1-phosphate.
The conformational behavior of methyl(2-O-methyl-alpha-L-rhamnopyranosyl)phosphate, together with a group of potentially more stable analogues, was investigated through a DFT approach at the B3LYP/6-31G(d) level; the energy of all the optimized structures was recalculated using a continuum solvent model, C-PCM, choosing water as the solvent. The compounds exhibited several, sometimes tenths of populated conformations so that the overall properties of flexibility and mobility were evaluated. The analogue in which the pyranose oxygen atom is replaced by a methylene group emerges as the best candidate as a mimic of the reference 1-phosphate, in spite of the fact that it lacks the anomeric and exo-anomeric effects. The other analogues result poorer mimics because of a conformational equilibrium at the pyranose ring or of an excessive rigidity of the aglycone moiety.
Compostella
Federica
F
Dipartimento di Chimica, Biochimica e Biotecnologie per la Medicina, Università di Milano, Via Saldini 50, 20133 Milano, Italy.
Albini
Franca Marinone
FM
Ronchetti
Fiamma
F
Toma
Lucio
L
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D008958:Models, Molecular; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D015394:Molecular Structure; D013403:Sugar Phosphates / Q000737:chemistry*; D014312:Trisaccharides / Q000737:chemistry
D013403:Sugar Phosphates; D014312:Trisaccharides; C494278:methyl (2-O-methylrhamnopyranosyl)phosphate