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Conformational study of the hydroxymethyl group in α-d-mannose derivatives

✍ Scribed by Chaxiraxi Nóbrega; Jesús T. Vázquez

Book ID
104360066
Publisher
Elsevier Science
Year
2003
Tongue
English
Weight
326 KB
Volume
14
Category
Article
ISSN
0957-4166

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✦ Synopsis

A study of the dependence of the hydroxymethyl group in a-D-mannose derivatives on the aglycon and its absolute configuration was performed by means of circular dichroism (CD) and NMR data. Depending mainly on the aglycon present, the gg or the gt rotamer was the most populated, the tg rotamer having a small population. In addition, the study showed a correlation between the rotational populations and the aglycon, the population of the gt rotamer increasing as the pK a of the bonded alcohol (aglycon) increased. Furthermore, the results revealed a strong dependence on the absolute configuration of the aglycon and point to the stereoelectronic exo-anomeric effect being responsible for these rotational dependencies besides nonbonding interactions.

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