Ritonavir: An Extraordinary Example of Conformational Polymorphism

  title={Ritonavir: An Extraordinary Example of Conformational Polymorphism},
  author={John F. Bauer and Stephen G. Spanton and Rodger F. Henry and John Quick and Walter Dziki and William Porter and John Morris},
  journal={Pharmaceutical Research},
AbstractPurpose. In the summer of 1998, Norvir semi-solid capsules supplies were threatened as a result of a new much less soluble crystal form of ritonavir. This report provides characterization of the two polymorphs and the structures and hydrogen bonding network for each form. Methods. Ritonavir polymorphism was investigated using solid state spectroscopy and microscopy techniques including solid state NMR, Near Infrared Spectroscopy, powder X-ray Diffraction and Single crystal X-ray. A… 
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