To a solution of 0.22 g (0.81 mmol) of 2-(benzylthio)-6,7-dihydroquinazolin-8(5H)-one in 5 mL of dry tetrahydrofuran cooled to −50° C., 0.10 g of sodium hydride 60% in mineral oil were added. The resulting suspension was maintained at the same temperature for 30 minutes and then 0.59 mL of ethyl α-oxobenzeneacetate (PhCOCOOEt) were added and the reaction mixture allowed to come to room temperature. After 16 hours the mixture was partitioned between water and ethyl acetate and the organic layer was dried over Na2SO4 and evaporated to dryness. The residue was purified by chromatography on a silica gel column (eluant hexane/ethyl acetate 7/3) giving 0.22 g (68% yield) of the title compound.
