Cocrystallization and configurations of myo-inositol-1,2-l-camphor acetals in two crystal structures

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}, C16H26O6, 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}, C16H26O6·3H2O, 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.