ISSN:
1600-5740
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
The three types of inclusion compounds of cholanamide (CAM, 3α, 7α, 12α-trihydroxy-5β-cholan-24-amide) have been crystallized from the solutions of (S)-butan-2-ol (CAMSB), (R)-butan-2-ol (CAMRB) and racemic butan-2-ol (CAMSRB), respectively. The crystal structures have been determined. The three crystal structures are isomorphous to each other and revealed that the host CAM molecules form the same layered arrangements, providing channel spaces for the guest butan-2-ol molecules. As expected, the CAMSB and CAMRB crystals include the pure (S)- and (R)-enantiomers of butan-2-ol, whereas the (S)-enriched mixture of enantiomers is accommodated in CAMSRB with a molar ratio between the host CAM and guest butan-2-ol molecules of 1:1. The hydrogen-bond network is rigidly formed between the CAM molecules and also between CAM and butan-2-ol molecules. CAMSB and CAMRB have slightly different unit-cell dimensions: the channels in CAMRB have a larger section, resulting in a larger unit-cell volume. In CAMSRB, although both enantiomers of the guest alcohol are included, the (S)-enantiomer is more abundant, indicating that the optical resolution occurs during the crystallization step.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0108768196004569
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