2,3:4,6-Di-O-isopropylidene-α-L-sorbofuranose and 2,3-O-isopropylidene-α-L-sorbofuranose

Abstract

In the title compounds, C(12)H(20)O(6), (I), and C(9)H(16)O(6), (II), the five-membered furanose ring adopts a (4)T(3) conformation and the five-membered 1,3-dioxolane ring adopts an E(3) conformation. The six-membered 1,3-dioxane ring in (I) adopts an almost ideal (O)C(3) conformation. The hydrogen-bonding patterns for these compounds differ substantially: (I) features just one intramolecular O-H...O hydrogen bond [O...O = 2.933 (3) A], whereas (II) exhibits, apart from the corresponding intramolecular O-H...O hydrogen bond [O...O = 2.7638 (13) A], two intermolecular bonds of this type [O...O = 2.7708 (13) and 2.7730 (12) A]. This study illustrates both the similarity between the conformations of furanose, 1,3-dioxolane and 1,3-dioxane rings in analogous isopropylidene-substituted carbohydrate structures and the only negligible influence of the presence of a 1,3-dioxane ring on the conformations of furanose and 1,3-dioxolane rings. In addition, in comparison with reported analogs, replacement of the -CH(2)OH group at the C1-furanose position by another group can considerably affect the conformation of the 1,3-dioxolane ring.

Tetrahedral and Octahedral Complexes of Mn2+ in the Aqueous Solutions of MNCL2.4H2O

“…We are investigated the aqueous solution of MnCl 2 .4H 2 O with different concentrations. Our experiment will be usefull for the clarification of the growth conditions of the crystals MgSO 3 .6H 2 O from aqueous solution [1,2]. These materials have application in the nonlinear optics.…”