South African Journal of Chemistry
versão On-line ISSN 1996-840X
BANUEIOS-HERNANDEZ, A.E. e MENDOZA-ESPINOZA, J.A.. Study of cyclization of diphenylacetals derived from L-rhamnose and L-fucose: A theoretical approach. S.Afr.j.chem. (Online) [online]. 2012, vol.65, pp. 84-90. ISSN 1996-840X.
This work aimed to study the configuration of two mono-tosyl-diphenylacetals, highly flexible molecules derived from L-ramnose and L-fucose, by means of the Monte Carlo conformational search method. The energy of the conformers established by this method and calculated by using the molecular mechanics force field (MMFF) permitted to establish a first conformational space. The geometry of the conformers was optimized by using the semi-empirical AM1 and the density functional B3LYP/DGDZVP methods. We were able to explain the different final products recovered from the reaction of the diphenylacetals derived from L-rhamnose and L-fucose with tosyl chloride, in a pyridine solution. On the other hand, obtaining cyclical compounds by intramolecular cyclization could be an attractive pathway for the synthesis of furanosides.
Palavras-chave : Molecular modelling; conformational analysis; Monte Carlo conformational search method; L-rhamnose; L-fucose; B3LYP; DGDZVP; diphenylthioacetal.