RESUMEN
Inclusion complexes (ICs) between alpha-cyclodextrin (alpha-CD) and three kinds of biodegradable aliphatic polyesters with different sequence lengths of the monomeric repeating units poly(3-hydroxypropionate) [P(3HP)], poly(4-hydroxybutyrate) [P(4HB)] and poly(epsilon-caprolactone)(PCL) were prepared by mixing a solution of alpha-CD with that of the polymer, followed by stirring. The ICs were obtained as insoluble precipitates and characterized by FT-IR, WAXD and DSC. All measurements showed that the polymer chains of all three kinds of polyester were included into the alpha-CD cavity and formed ICs with different stoichiometries. WAXD patterns and thermal analysis indicated that these ICs possessed a channel structure and the crystallization of the polyester chains was suppressed upon inclusion into the alpha-CD cavity.
Asunto(s)
Poliésteres/química , alfa-Ciclodextrinas/síntesis química , Biodegradación Ambiental , Rastreo Diferencial de Calorimetría , Cristalización , Enlace de Hidrógeno , Sustancias Macromoleculares , Espectroscopía de Resonancia Magnética , Poliésteres/síntesis química , Poliésteres/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Difracción de Rayos X , alfa-Ciclodextrinas/análisis , alfa-Ciclodextrinas/química , alfa-Ciclodextrinas/metabolismoRESUMEN
The reaction of N-aryl-substituted ketenimines with N,N-disubstituted cyanamides or (MeS)2C=N-CN under high pressure afforded 4-(N,N-disubstituted amino) or 4-(MeS)2C=N-substituted quinazoline derivatives, respectively. These products were formed by [4+2] cycloaddition between the aza-diene moieties of the N-arylsubstituted ketenimines and cyano groups. A 4-(unsubstituted amino)quinazoline derivative was synthesized by hydrolysis of the latter product.
