CRYSTAL AND MOLECULAR-STRUCTURES OF PENTA-O-ACETYL-ALDEHYDO-D-GLUCOSEDIMETHYL ACETAL AND OF HEPTA-O-ACETYL-ALDEHYDO-D-GLUCOSE HYDRATE

The solid-state structures of the title compounds were determined by c onventional single-crystal X-ray crystallography. In both cases a plan ar zigzag conformation of the carbon skeleton is observed with a resul ting 1,3-parallel orientation of O(2) and O(4). In the case of the hep taacetate even a second such arrangement is established between O(3) a nd one of the oxygens at C(1). These findings substantiate the claim t hat such conformations are not as unfavourable as previously was assum ed by many authors.