Cynarine monohydrate from synchrotron powder X‐ray diffraction data. Issue 2 (25th January 2022)

• Record Type: Journal Article
• Authors: Kaduk, James A.; Boaz, Nicholas C.; Markun, Emma L.; Gindhart, Amy M.; Blanton, Thomas N.
• Is Part Of: Acta crystallographica. Volume 78:Issue 2(2022)
• Page Start: 101
• Page End: 106
• Publication Date: 2022-01-25
• Subjects: powder diffraction -- cynarine -- 1, 5‐dicaffeoylquinic acid -- Rietveld refinement -- density functional theory -- crystal structure; Crystallography -- Periodicals; Crystals -- Periodicals; 548.3
• DOI: 10.1107/S2053229622000687
• Languages: English
• ISSNs: 2053-2296

Abstract

Abstract : The crystal structure of cynarine monohydrate has been solved and refined using synchrotron powder X‐ray diffraction data and optimized using density functional techniques. Abstract : The crystal structure of cynarine monohydrate (systematic name: 1, 3‐bis{[( E )‐3‐(3, 4‐dihydroxyphenyl)prop‐2‐enoyl]oxy}‐4, 5‐dihydroxycyclohexane‐1‐carboxylic acid monohydrate), C25 H24 O12 ·H2 O, has been solved and refined using synchrotron powder X‐ray diffraction data, and optimized using density functional techniques. Despite being purchased as anhydrous, cynarine crystallizes as a monohydrate and the crystal structure is characterized by alternating layers of hydrocarbon and hydrogen‐bonding interactions parallel to the bc plane. Hydrogen bonds are significant in the crystal structure. The carboxylic acid group forms a strong intermolecular hydrogen bond to a hydroxy group of the quinic acid ring. Most of the hydroxy groups act as donors in O—H…O hydrogen bonding to carbonyl O atoms. One hydroxy group participates in bifurcated hydrogen bonds, one to a hydroxy group on the quinic acid ring and the other, an intramolecular interaction, to another hydroxy group. The powder pattern has been submitted to the International Centre for Diffraction Data (ICDD) for inclusion in the Powder Diffraction File (PDF‐4).