Nonamorphism in flufenamic acid and a new record for a polymorphic compound with solved structures.
The unprecedented polymorphism of the non-steroidal anti-inflammatory drug (NSAID) flufenamic acid (FFA) is described here. Nine polymorphs were accessed through the use of polymer-induced heteronucleation (PIHn) and solid-solid transformation at low temperature. Structural elucidation of six of these forms, in addition to the two previously known forms, makes FFA indisputably octamorphic. Although the structure of at least one other form of FFA remains elusive, the occurrence of most of these polymorphs under one crystallization condition through PIHn illustrates that a fine interplay exists among the kinetic factors that lead to phase selection in this NSAID.
Department of Chemistry and the Macromolecular Science and Engineering Program, University of Michigan-Ann Arbor, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, USA.
Vilmalí
V
López-Mejías
Jeff W
JW
Kampf
Adam J
AJ
Matzger
D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D003460:Crystallization; D005439:Flufenamic Acid / Q000737:chemistry*; D008958:Models, Molecular
D000894:Anti-Inflammatory Agents, Non-Steroidal; D005439:Flufenamic Acid