IFEG   20353
INSTITUTO DE FISICA ENRIQUE GAVIOLA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
2D solid state homonuclear and heteronuclear correlation experiments to study a new pharmaceutical compound
Autor/es:
Y. GARRO LINCK; A.K CHATTAH; C. ROMAÑUK; M.E. OLIVERA; R.H. MANZO; S.L. CUFFINI; R. GRAF; G.A. MONTI; H.W. SPIESS
Lugar:
Göteborg, Suecia
Reunión:
Conferencia; EUROMAR Magnetic Resonance Conference; 2009
Resumen:
<!-- /* Font Definitions */ @font-face {font-family:Helvetica; panose-1:2 11 6 4 2 2 2 2 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:7 0 0 0 147 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; mso-layout-grid-align:none; punctuation-wrap:simple; text-autospace:none; font-size:10.0pt; font-family:Helvetica; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:Helvetica;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Ciprofloxacin is a widely prescribed broad-spectrum oral fluoroquinolone antibiotic. Low solubility and bitter taste are unfavorable properties associated with most fluoroquinolones that limit their formulation. Saccharine (SAC) derivatives, either as salts or co-crystals, show an improved solubility behavior and better taste. [Romañuk et al. J. Pharm. Sci. DOI: 10.1002/jps.2168] Advanced solid states nuclear magnetic resonance (NMR) techniques have been used to study a new pharmaceutical compound, the ciprofloxacin saccharinate, CIP-SAC. This compound has been previously reported and fully characterized with a variety of solid state techniques (IR, DSC, XRD and 13C CP-MAS NMR). This saccharinate evidences polymorphism presenting two well distinguished solid forms, CIP-SAC (I) and (II). In this work we have performed 2D 13C-1H heteronuclear correlation experiments (REPT-HSQC and HETCOR) which allowed the complete assignment of the resolved 1H solid state spectrum. [Schnell et al. J. Mag. Reson. 150, 57–70 (2001) and van Rossum et al. J. Mag. Reson. 124, 516–519 (1997)] These data were complemented with double quantum MAS experiments (BABA pulse sequence [Schnell et al. J. Mag. Reson. 133, 61–69 (1998)]) to identify 1H-1H connectivities, hydrogen bonds and dipolar proximities. The zwitterionic character of ciprofloxacin and its derivative was identified. Further information about inter and intra molecular interactions in both solid forms of the new saccharinate was obtained. Differences and similarities in the structures of the different solid forms have also been established and supported with single crystal XR diffraction data obtained for CIP-SAC (II).