5-bromouracil derivatives ( 1 ) reacted with carbanions at room temperature to give 6-substituted uracils ( 6 ) , 2,4-diazabicyclo [ 4,1,0 ] heptanes ( 8 ) and 2,4-diazabicyclo [ 4,3,0 ] nonane derivative ( 9 ) , which depend largely upon the structure of the active methylene compounds employed for the generation of carbanions .
C0006242
5-bromouracil
C0041917
uracils