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Updated: Feb 10, 2026
Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
Structural studies of crystalline forms of triamterene with carboxylic acid, GRAS and API molecules
Abida Rehman1, Amit Delori2, David S Hughes1
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, Cambridgeshire CB2 1EW, England.
Abstract:
Pharmaceutical salt solvates (dimethyl sulfoxide, DMSO) of the drug triamterene with the coformers acetic, succinic, adipic, pimelic, azelaic and nicotinic acid and ibuprofen are prepared by liquid-assisted grinding and solvent-evaporative crystallization. The modified ΔpKa rule as proposed by Cruz-Cabeza [(2012 ▸). CrystEngComm, 14, 6362-6365] is in close agreement with the results of this study. All adducts were characterized by X-ray diffraction and thermal analytical techniques, including single-crystal X-ray diffraction, powder X-ray diffraction, differential scanning calorimetry and thermal gravimetric analysis. Hydrogen-bonded motifs combined to form a variety of extended tapes and sheets. Analysis of the crystal structures showed that all adducts existed as salt solvates and contained the amino-pyridinium-carboxyl-ate heterodimer, except for the solvate containing triamterene, ibuprofen and DMSO, as a result of the presence of a strong and stable hemitriamterenium duplex. A search of the Cambridge Structural Database (CSD 5.36, Version 1.18) to determine the frequency of occurrence of the putative supramolecular synthons found in this study showed good agreement with previous work.
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