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Updated: May 27, 2026

Thermostabilization, Expression, Purification, and Crystallization of the Human Serotonin Transporter Bound to S-citalopram
Published on: November 27, 2016
Polymorphism and a metastable solvate of duloxetine hydrochloride
Christopher E Marjo1, Mohan Bhadbhade, James M Hook
1Mark Wainwright Analytical Centre, Room G61, Chemical Sciences Building (F10), University of New South Wales, Kensington, New South Wales, Australia 2052. c.marjo@unsw.edu.au
Abstract:
Duloxetine hydrochloride (1) is an important antidepressant that acts as a serotonin and noradrenaline reuptake inhibitor that has only recently been characterized by single-crystal X-ray diffraction. This study describes an investigation into polymorphism of duloxetine hydrochloride, discusses the challenges of characterizing new structures, and reports a new metastable solvate (1(acetone)) where acetone is trapped in a duloxetine hydrochloride host lattice. In view of the importance of formulation processing and bioavailability characteristics of the crystalline forms of 1, a comprehensive structural study of 1(acetone) was carried out using single-crystal and powder X-ray diffraction, infrared and Raman spectroscopies, and solid-state NMR spectroscopy. The rapid desolvation from 1(acetone) to the stable unsolvated form was investigated, and the structures of free and solvated forms are discussed in terms of the noncovalent intermolecular interactions.
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