To a stirred solution of 5-benzyloxy-2-[1-(4-chlorophenyl)-cyclopentylmethyl]-6-hydroxypyrimidine-4-carboxylic acid [2-(tert-butyl-dimethylsilanyloxy)-ethyl]-(tetrahydro-pyran-4-yl)-amide (333) in tetrahydrofuran (3 ml) was added 1N HCl (1 ml) at room temperature and the reaction mixture was stirred for 30 min at room temperature while silica thin layer chromatography was performed (ethyl acetate:hexane=3:2, Rf=0.4). After completion of the reaction, solid NaHCO3 was added and the mixture basified up to about pH 8. After extraction with ethyl acetate (3×30 mL), the combined extracts were dried and concentrated to get 5-benzyloxy-2-[1-(4-chlorophenyl)-cyclopentylmethyl]-6-hydroxypyrimidine-4-carboxylic acid (2-hydroxyethyl)-(tetrahydro-pyran-4-yl)-amide (334) which was used in the next step without purification.
