Water-mediated intermolecular interactions in 1,2-O-cyclohexylidene-myo-inositol: a quantitative analysis

Acta Crystallogr C Struct Chem. 2017 Jan 1;73(Pt 1):20-27. doi: 10.1107/S2053229616018581. Epub 2017 Jan 1.

Abstract

The syntheses of new myo-inositol derivatives have received much attention due to their important biological activities. 1,2-O-Cyclohexylidene-myo-inositol is an important intermediate formed during the syntheses of certain myo-inositol derivatives. We report herein the crystal structure of 1,2-O-cyclohexylidene-myo-inositol dihydrate, C12H20O6·2H2O, which is an intermediate formed during the syntheses of myo-inositol phosphate derivatives, to demonstrate the participation of water molecules and hydroxy groups in the formation of several intermolecular O-H...O interactions, and to determine a low-energy conformation. The title myo-inositol derivative crystallizes with two water molecules in the asymmetric unit in the space group C2/c, with Z = 8. The water molecules facilitate the formation of an extensive O-H...O hydrogen-bonding network that assists in the formation of a dense crystal packing. Furthermore, geometrical optimization and frequency analysis was carried out using density functional theory (DFT) calculations with B3LYP hybrid functionals and 6-31G(d), 6-31G(d,p) and 6-311G(d,p) basis sets. The theoretical and experimental structures were found to be very similar, with only slight deviations. The intermolecular interactions were quantitatively analysed using Hirshfeld surface analysis and 2D (two-dimensional) fingerplot plots, and the total lattice energy was calculated.

Keywords: Hirshfeld surface analysis; crystal structure; geometry optimization; lattice energy; myo-inositol; potential chemotherapeutic agent; transmembrane signalling.