Methanol → (+/-)-5-[[5-(2-Ethyl-7-methyl-4H-benzo[5,6]cyclohepta[1,2-d]oxazol-4-yl)-3,4-dihydro-2,4-dioxo-1(2H)-pyrimidinyl]methyl]-2-furancarboxylic acid, ethyl ester

Beteiligte Stoffe

Reaktionsschritte

To a slurry of the product of step (vii) (1.42 g) in dry 1,2-dichloroethane (15 ml) was added bis(trimethylsilyl)trifluoroacetamide (3.4 ml). The mixture was heated at reflux for 2 hours until the mixture became a homogeneous solution. The solution was allowed to cool to room temperature and a solution of 5-[bromomethyl]-2-furancarboxylic acid ethyl ester (J. Chem. Soc. Perkin Trans. 1, 1981, 1125, Bull. Chem. Soc. Jpn., 1987, 60, 1807) (1.1 g) in dry acetonitrile (15 ml) was added. The solution was then heated at reflux for 14 hours. The reaction mixture was allowed to cool and methanol (15 ml) was added. The solvents were evaporated under reduced pressure and the residue was triturated with diethyl ether. The resultant solid was collected by filtration and partitioned between saturated aqueous sodium bicarbonate and ethyl acetate. The organic phase was dried (MgSO4) and the solvent was evaporated under reduced pressure. Purification was by chromatography eluting with ethyl acetate.

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