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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Crystal engineering of a zwitterionic drug to neutral cocrystals: a general solution for floxacins
Anilkumar Gunnam1, Kuthuru Suresh1, Ramesh Ganduri2
1School of Chemistry, University of Hyderabad, Prof. C. R. Rao Road, Gachibowli Central University P.O., Hyderabad 500046, India. ashwini.nangia@gmail.com.
Abstract:
The transformation of zwitterionic Sparfloxacin (SPX) to the neutral form is achieved by cocrystallization. Neutral forms of drugs are important for higher membrane permeability, while zwitterions are more soluble in water. The twin advantages of higher solubility/dissolution rate and good stability of neutral SPX are achieved in a molecular cocrystal compared to its zwitterionic SPX hydrate. The amine-phenol supramolecular synthon drives cocrystal formation, with the paraben ester acting as a "proton migrator" for the ionic to neutral transformation.
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