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Aplicación de RMN de estado sólido de 35Cl a la caracterización estructural de productos farmacéuticos de clorhidrato

Hiyam Hamaed¹, Jenna M Pawlowski, Benjamin F T Cooper

¹Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada N9B 3P4.

Journal of the American Chemical Society

|July 29, 2008

Resumen

La espectroscopia de RMN de estado sólido (35) Cl examina eficazmente la estructura y el polimorfismo en los productos farmacéuticos HCl. Esta técnica proporciona una rápida identificación e interpretación estructural de diferentes formas cristalinas, ayudando al desarrollo farmacéutico.

Área de la Ciencia:

Espectroscopia de RMN en estado sólido Espectroscopia de RMN en estado sólido
Ciencias Farmacéuticas Ciencias Farmacéuticas
La cristalografía es una técnica de cristalografía.

Sus antecedentes:

Las sales de ácido clorhídrico (HCl) forman aproximadamente el 50% de las sales farmacéuticas conocidas.
Comprender el polimorfismo es crucial para la eficacia y seguridad de los fármacos.
La espectroscopia de RMN de estado sólido (35) Cl (SSNMR) ofrece un método potencial para caracterizar estos compuestos.

Objetivo del estudio:

Evaluar la utilidad de la espectroscopia SSNMR de (35) Cl para analizar la estructura y el polimorfismo de los productos farmacéuticos de HCl.
Para correlacionar los parámetros de SSNMR con datos cristalográficos y resultados computacionales.
Para demostrar la aplicación de (35) Cl SSNMR como una técnica de huellas dactilares para la identificación de polimorfos.

Principales métodos:

Adquisición de espectros de (35) Cl Magic Angle Spinning (MAS) de SSNMR en campos magnéticos altos (21.1 T). adquisición de espectros de (35) Cl Magic Angle Spinning (MAS) de SSNMR en campos magnéticos altos (21.1 T). adquisición de espectros de (35) Cl en campos magnéticos altos (21.1 T). adquisición de espectros de (35) Cl en campos magnéticos altos (21.1 T). adquisición de espectros de (35) Cl en campos magnéticos altos (21.1 T).
Espectro de registro de muestras estacionarias en campos magnéticos variables (9.4 y 21.1 T).
Utilizando un solo cristal y difracción de rayos X de polvo, junto con cálculos ab initio para el análisis complementario.

Principales resultados:

(35) Los espectros de Cl SSNMR revelaron sensibilidad a cambios ambientales sutiles, reflejados en los parámetros de gradiente de campo eléctrico (EFG) y desplazamiento químico (CS).
Los patrones de polvo de SSNMR sirvieron como una huella digital rápida para distinguir los polimorfos.
Los parámetros del tensor experimentales (35) Cl EFG y CS mostraron una buena concordancia con los cálculos de los primeros principios.

Conclusiones:

(35) La espectroscopia de Cl SSNMR es una herramienta valiosa para la interpretación estructural y la identificación de polimorfos en productos farmacéuticos de HCl.
La sensibilidad de la técnica y la precisión del modelado ab initio muestran una promesa significativa para una amplia aplicación en el cribado polimórfico farmacéutico.

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