Analysis of fructofuranose conformations by molecular mechanics

Energies for various envelope and twist conformers of α‐ and β‐D‐fructofuranose (FF) have been calculated with MMP2 (85). Values of low energy are found near T conformations, and, secondarily, to ranges near T shapes. α‐D‐FF has a path through the 0E form for transitions between forms, as found by other workers for β‐D‐ribose, while the slightly preferred transition for β‐D‐FF is through the 0E conformer. The majority of conformations of β‐D‐FF that have been determined by single‐crystal diffraction studies are in a fairly deep well, with energy values less than 0.5 kcal / mol above the minimum.