Cocrystallization and configurations ofmyo-inositol-1,2-L-camphor acetals in two crystal structures

Abstract

The inositol rings in (1S,2R,3R,4S,5S,6R,7S,8S,11S)-myo-inositol-1,2-camphor acetal {systematic name: (1R,2S,3S,4R,5S,6R)-5,6-[(1S,2S,4S)-1,7,7-trimethylbicyclo[2.2.1]heptane-2,2-diyldioxy]cyclohexane-1,2,3,4-tetrol}, C(16)H(26)O(6), and (1R,2S,3S,4R,5R,6S,7R/S,8S,11S)-myo-inositol-1,2-camphor acetal trihydrate {systematic name: (1S,2R,3R,4S,5R,6S)-5,6-[(1S,4S,6R/S)-1,7,7-trimethylbicyclo[2.2.1]heptane-2,2-diyldioxy]cyclohexane-1,2,3,4-tetrol trihydrate}, C(16)H(26)O(6).3H(2)O, adopt flattened chair conformations with the latter crystal containing two stereoisomers in a 0.684 (2):0.316 (2) ratio, similar to that found both in solution and by calculation. Both molecules pack in the crystals in similar two-dimensional layers, utilizing strong O-H...O hydrogen bonds, with the trihydrate cell expanded to incorporate the additional hydrogen-bonded water molecules.

The role of hydrogen bonding in the incommensurate modulation of myo-inositol camphor ketal

“…The basic structure has C2 symmetry with one crystallographically unique molecule of 1 located in a general position. In principle, it corresponds well to the structure of the enantiomorph of 1 published by Gainsford et al (2007), though the latter has enlarged ADPs since it corresponds to the average structure and therefore the ADPs reflect the variance of the atomic positions in the modulated structure.…”

“…6). If both hydrogen bonds were realized simultaneously, a short HÁ Á ÁH contact of ca 1.66 Å as reported by Gainsford et al (2007) would be realized. Thus, starting from a given 1 molecule, either O3!O6 or O4!O6 will be assumed and the hydrogenbonding network traced therefrom.…”

“…The crystal structure at 170 K of the enantiomer of 1, myoinositol-1,2-l-camphor ketal [ Fig. 1(b)], has previously been described by Gainsford et al (2007). However, these authors neither report signs of modulation nor a disordered hydrogen-bonding network.…”

“…The practically noiseless detector combined with a high-intensity microfocused beam provided the dynamic range (> 10 6 ) necessary for the intensity evaluation of higher-order satellites. Structural formula of (a) 1 and (b) its enantiomer described by Gainsford et al (2007). (3kl)* plane of reciprocal space of a crystal of 1 reconstructed from 2D detector data.…”

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

“…It is very interesting to see that most substructures, i.e. nine, are found in the anhydrous form; the remaining structure is myo-inositol-1,2-camphor acetal trihydrate (Gainsford et al, 2007). The CSD similar-structure search for (1) gave 1320 hits with a minimum similarity coefficient (MSC) cut-off of 0.7.…”