Process for preparing a 2-(2-amino-1,6-dihydro-6-oxo-purin-9-yl)methoxy-1,3-propanediol derivative

摘要

Process and novel intermediates for preparing the mono-L-valine ester of 2-(2-amino-1,6-dihydro-6-oxo-purin-9-yl)methoxy-1,3-propanediol ganciclovir) and its pharmaceutically acceptable salts. The present process and monoester intermediates provide for mono-esterification by an L-valine derivative, resulting in a monocarboxylate-monovalinate which is then selectively hydrolyzed under basic or enzymatic conditions to give the monovaline ester of ganciclovir in high yield and purity. These products are of value as antiviral agents with improved absorption.