1(2H)-Pyrimidinepropanoic acid, 5-fluoro-3,4-dihydro- 2,4-dioxo-, ester with .omega.-methyl-.alpha.-hydroxypoly (oxy-1,2-ethanediyl) NSC381811 Poly(oxy-1,2-ethanediyl), .alpha.-methyl-.omega.-[[3- (5-fluoro-1,2,3,4-tetrahydro-2,4-dioxo-1-pyrimidinyl)- 1-oxopropyl]oxy]-