The treatment of 5-(4-chlorobutanoyl)-1,3-dimethylbarbituric acid (1) with
K2CO3 furnishes a 5-(tetrahydrofuran-2-ylidene)barbituric acid derivative 2
. A similar reaction of 5-chloroacetyl-1,3-dimethylbarbituric acid (4) with
Et3N yields a furanouracil 5. Synthetic transformations of 2 and 5 to 5-(o
mega-heteroarylalkanoyl)-1,3-dimethylbarbituric acids and synthesis of othe
r furanouracils from 5 are described.