Abstract:
The invention refers to a method for isolating entecavir or an entecavir intermediate from a diluted mixture, the diluted mixture comprising entecavir and water or a mixture comprising an entecavir intermediate and other process reagents comprising: (a) adsorbing the diluted mixture onto a hydrophobic resin bed; (b) washing the resin bed with water to remove salt; and (c) eluting the entecavir or entecavir intermediate from the resin bed with an organic solvent.
Abstract:
The present invention concerns a process for the stereoselective enzymatic reduction of keto group-containing compounds such as N-(4-(2-chloroacetyl)phenyl)methanesulfonamido to form the corresponding hydroxyl-group containing compound. The process is selective for the D(+) enantiomer and is catalyzed by enzymes such as oxido-reductase or dehydrogense, or by microorganisms such as Hansenula, Rhodococcus, or Norcardia species.
Abstract:
The present invention concerns a process for the stereoselective enzymatic reduction of keto group-containing compounds such as N-(4-(2-chloroacetyl)phenyl)methanesulfon-amido to form the corresponding hydroxyl-group containing compound. The process is selective for the D(+) enantiomer and is catalyzed by enzymes such as oxido-reductase or dehydrogense, or by microorganisms such as Hansenula, Rhodococcus, or Norcardia species.
Abstract:
The present invention concerns a process for the stereoselective enzymatic reduction of keto group-containing compounds such as N-(4-(2-chloroacetyl)phenyl)methanesulfonamido to form the corresponding hydroxyl-group containing compound. The process is selective for the D(+) enantiomer and is catalyzed by enzymes such as oxido-reductase or dehydrogense, or by microorganisms such as Hansenula, Rhodococcus, or Norcardia species.
Abstract:
Un procedimiento para preparar entecavir que tiene la fórmula que comprende: (a) tratar un éster de la fórmula en la que Ra es alilo, fenilo, alquilfenilo C1 a C6, o alcoxifenilo C1 a C6; Rb es alquilo C1 a C6; y R es alquilo C1 aC4 o bencilo; con un enol éter de acetona y un ácido para proteger el grupo hidroxi, seguido de tratamiento con un reactivo dehidruro para reducir el resto de éster de ácido carboxílico, y a continuación alquilar el alcohol resultante con unhaluro de bencilo y eliminar el grupo protector hidroxi enol éter para dar un alcohol alílico de la fórmula (b) epoxidar el producto de la etapa (a) con una epoxidación diastereoselectiva para dar un epóxido deciclopentano que tiene la fórmula (c) tratar el epóxido de ciclopentano de la etapa (b) con una sal de metal alcalino de un compuesto de purina defórmula