Successful prediction of the hydrogen bond network of the 3-oxo-12α-hydroxy-5β-cholan-24-oic acid crystal from resolution of the crystal structure of deoxycholic acid and its three 3,12-dihydroxy epimers

A Standard Structure for Bile Acids and Derivatives

“…It can be concluded from these studies that the solid state structure depends on subtle differences in donor-acceptor relationships among the hydrogen bonding groups of guest and steroid molecules. The solution of the crystal structures of the four 3,12-dihydroxy epimers of DCA was used to successfully predict the hydrogen bond network of the 3-oxo-12α-hydroxy derivative [8]. On the other hand, the ability to form hydrogen bonds by CA plus the characteristics of head-to-head dimers have been used for designing a crystal, in which a single water molecule is encapsulated between two cholic residues in an ice-like structure [17].…”

“…Bile acids (BA) are compounds resulting from the protonation of the carboxylate group of BS, and can be conjugated with the amino acids glycine and taurine. Those corresponding to cholic (CA, 1, Table 1), lithocholic (2), deoxycholic (DCA, 3), chenodeoxycholic (7), and ursodeoxycholic (8) acids are among the most important and studied BA. The orientation of the OH substituents is such that BS are facially amphipathic molecules with three-axial chirality [3] that self-aggregate in aqueous solution, forming aggregates, which usually have low aggregation numbers [4,5].…”

“…Crystals 2018, 8,86 11 of 17 Table 6. Mean values and standard deviations for the bond angles of the steroids analyzed in this paper, and comparison with progesterone and the lateral chain of cholesterol.…”

Supramolecular Structures Generated by a p-tert-Butylphenylamide Derivative of Deoxycholic Acid. From Planar Sheets to Tubular Structures through Helical Ribbons

“…[18][19][20] On the other hand, we have to remind that the physicochemical properties of the natural bile salts are highly dependent on the number, location and stereochemistry of the hydroxyl groups. 34,[39][40][41] In short, these effects may be referred to simply as "hydroxyl effect". For instance, the only structural difference between NaC and sodium deoxycholate (NaDC) is the existence or not of a hydroxyl group at C7.…”

Additional criterion for the determination of the handedness of 21 helices in crystals of bile acids: Crystal structure of a tert‐butylphenyl derivative of cholic acid

“…Most of the systematic studies on bile acid crystals have used a large variety of solvents and guests, but others have focused their attention on different derivatives of bile acids. Among them, we can mention compounds resulting from the increase17 or decrease18, 19 of the number of methylene units constituting the lateral chain of bile acids, amide20 and ester derivatives of their carboxylic group or amides,21, 22 esters,23 and keto derivatives24, 25 of their hydroxy group, as well as the epimerization of the carbon atoms where this last function is attached 26, 27. From these studies, it can be concluded that the solid state structure depends on subtle differences in donor–acceptor relationships among the hydrogen bonding groups belonging to guests and steroid molecules.…”