Abstract: 2-Phthalimidoethyl-2-sulfur-1,3,2-dioxaphopholane(1) and cyclic glycerothiophospholipid conjugate of phahalimidoethanol(2) were used as model compounds to investigate the selectivity and reaction conditions of nucleophilic opening ring by heteroatomic function groups.CH₃OH could attack the phosphor atom in 1,3,2-dioxaphopholane of compiound(1) to give O-methyl O-hydroxyethyl-O-phthalimidoethyl thiophosphate in 85% yield;in the presence of potassium hydroxide aryl selenol could attack the carbon atom in 1,3,2-dioxaphopholane of the cyclic phospholipid conjugate of N¹-(2-furanidyl)-N³-(hydroxyalkyl)-5-fluorouracil to give the corresponding product of ring-opening in high yields.It was indicated through in vitro biological assays by using MTT that the title compound exhibited higher inhibitory effect on the malignant proliferation of bladder cancer cell T-24 and stomach cancer cell BGC-823 than tegafur,but on the other hand it showed a higher toxicity on the normal liver epithelial cell L-02.

Key words: Tegafur, Cyclic phospholipid conjugate of N₁-(2-furanidyl)-N₃-(hydroxyalkyl)-5-fluorouracil, Selective nucleophilic ring-opening, Aryl selenol, Glycerol phospholipid, Biologic activitiy