The aim of this work was to search for new polymorphic forms of febantel, an anthelminthic drug of great present interest for the veterinary industry. Solvent-based recrystn., thermal and mech. treatments and spray drying were chosen to discover new solid forms. The solids obtained were physicochem. characterized by thermal techniques (DSC and TG), FTIR spectroscopy, lab. and synchrotron X-ray powder diffraction and SEM. Our work leads to obtain a new solid form never described in the literature. In particular, the new polymorph was obtained by the anti-solvent method and the crystn. from isopropanol. The exptl. conditions of crystn. favorable to the formation of the highest amt. of the new solid phase were selected. The new phase shows a thermal, spectroscopic and diffractometric behavior unique. Furthermore, the preliminary structure investigation suggests two possible crystal systems: an orthorhombic or a monoclinic one, with really comparable lattice parameters and cell vol. Measurements put into evidence that the new phase is a metastable polymorph that is in monotropic relationship with the stable and known form.
Febantel: looking for new polymorphs
BRUNI, GIOVANNA;PARDI, FRANCESCA;CAPSONI, DORETTA;BERBENNI, VITTORIO;BINI, MARCELLA;MILANESE, CHIARA;GIRELLA, ALESSANDRO;MARINI, AMEDEO
2017-01-01
Abstract
The aim of this work was to search for new polymorphic forms of febantel, an anthelminthic drug of great present interest for the veterinary industry. Solvent-based recrystn., thermal and mech. treatments and spray drying were chosen to discover new solid forms. The solids obtained were physicochem. characterized by thermal techniques (DSC and TG), FTIR spectroscopy, lab. and synchrotron X-ray powder diffraction and SEM. Our work leads to obtain a new solid form never described in the literature. In particular, the new polymorph was obtained by the anti-solvent method and the crystn. from isopropanol. The exptl. conditions of crystn. favorable to the formation of the highest amt. of the new solid phase were selected. The new phase shows a thermal, spectroscopic and diffractometric behavior unique. Furthermore, the preliminary structure investigation suggests two possible crystal systems: an orthorhombic or a monoclinic one, with really comparable lattice parameters and cell vol. Measurements put into evidence that the new phase is a metastable polymorph that is in monotropic relationship with the stable and known form.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
