Comparison of racemicepi-inosose and (−)-epi-inosose

Abstract

The conversion of myo‐inositol to epi‐inositol can be achieved by the hydride reduction of an intermediate epi‐inosose derived from myo‐inositol. (−)‐epi‐Inosose, (I), crystallized in the monoclinic space group P21, with two independent molecules in the asymmetric unit [Hosomi et al. (2000). Acta Cryst. C56, e584–e585]. On the other hand, (2RS,3SR,5SR,6SR)‐epi‐inosose, C6H10O6, (II), crystallized in the orthorhombic space group Pca21. Interestingly, the conformation of the molecules in the two structures is nearly the same, the only difference being the orientation of the C‐3 and C‐4 hydroxy H atoms. As a result, the molecular organization achieved mainly through strong O—H...O hydrogen bonding in the racemic and homochiral lattices is similar. The compound also follows Wallach's rule, in that the racemic crystals are denser than the optically active form.

Сhiral and Racemic Fields Concept for Understanding of the Homochirality Origin, Asymmetric Catalysis, Chiral Superstructure Formation from Achiral Molecules, and B-Z DNA Conformational Transition

“…The simplest explanation of Wallach's phenomenon is associated with a difference in hydrogen bonding energies of "true" racemates and pure enantiomers [253][254][255][256][257][258][259][260]. Opponents of this concept validity believe that "true" racemates and pure enantiomers with analogous H-bonding are not rare in occurrence [261][262][263][264][265][266]. The discussion is complicated by the fact that there are the examples of anti-Wallach's rule [267].…”