Venlafaxine besylate monohydrate

Abstract

The title compound {systematic name: [2-(1-hydroxycyclohexyl)-2-(4-methoxyphenyl)ethyl]dimethylazanium benzene­sulfonate monohydrate}, C17H28NO2 +·C6H5O3S−·H2O, is a besylate salt hydrate of the anti­depressant drug venlafaxine. In the crystal, besylate anions and water mol­ecules self-assemble, forming hydrogen-bonded dimers linked around inversion centers, with graph set R 4 4(6). The crystal packing features a chain of alternate dimers and venlafaxine cations in the b-axis direction with the components linked by O—H⋯O hydrogen bonds and C—H⋯O and C—H⋯π inter­actions. This is the first example of a venlafaxine cation with a closed conformation, as it features an intra­molecular N—H⋯O inter­action involving the protonated N atom.

Computational, Spectral, and Bioavailability Studies of Venlafaxine Cyclic Impurity

“…The cyclohexane ring is in the stable chair conformation with bond angles hovering around 110° while the heterocyclic ring also appears to be more or less in chair conformation with bond angles ranging from 108.5 to 113°. The geometrical parameters were then compared against that of experimental values of VEN available in the literature, due to its structural similarity (26,27). There were slight deviations in the bond lengths and bond angles of VEN and VEN-CI due to the cyclization of the latter molecule.…”

“…Capillary electrochromatography (24) and LCMS/MS (25) were used in the past for the separation of VEN from ODV. The crystal structures of VEN in its chloride (26) and besylate forms (27) were studied in the past. To the best of our knowledge, the structure, properties, and assaying techniques of the title molecule have not been explored yet.…”

Versatile Salts as a Strategy to Modify the Biopharmaceutical Properties of Venlafaxine and a Potential Hypoglycemic Effect Study

“…Meanwhile, we noticed that the 13 C chemical shift changes of the N bonded C14 site may be used as such an indicator, because this methylene 13 C signal is less affected by molecular packing changes, and the protonation of the dimethylamino N site should be the main contributor for the chemical environmental altering. The proton transfer from a salt former to the dimethylamino group leads to a larger 15 N chemical shift, i.e., a reduced shielding effect on the N site. 20 Then, an enhanced shielding effect on the N bonded C14 site (smaller 13 C chemical shift) is desired.…”

“…13 Three polymorphs of venlafaxine were reported by van Eupen, 14 and one venlafaxine besylate monohydrate was reported by Corvalan. 15 Synthesis and structure of venlafaxine hydrochloride, 16,17 venlafaxine hydrobromide salt, 18 and venlafaxine saccharin salts 19 were reported.…”