Abstract: O-Alkyl-3-N-(methyl 2′, 3′, 4′-tri-O-acetyl-β-D-glucopyranuronate-1′-yl)-5- fluorouracil 3_e-c were synthesized by condensation of methyl 2, 3, 4-tri-O-acetyl-1-bromo-1-deoxy-α-D-glucopyranuronate 1 with 2-O-alkyl-5-fluorouracil 2_a(or 2_b, 2_c ) under phase transfer catalysis. Deacetylation of compounds 3_a-c with sodium methoxide in methanol gave 2-O-substituted-3-N(methyl β-D-glucopyranuronate-1′-yl)-5-fluorouracil 4_a-c respectively. After the treatment of compounds 3_a-c with ammonia in methanol 2-O-substituted-3-N-(β- D-glucopyranuronamide-1′-yl )-5-fluorouracil 4_e-cwere obtained. Debenzylation of 3_a, 4_a and 4_a′ by catalytic hydrogenolysis with 10%palladium-carbon in methanol gave 3-N-methyl 2′, 3′, 4′-tri-O-acetyl-β-D-glucopyranuronate-1′-yl)-5-fluorouracil 6_a, 3-N-(methyl β-D-glucopyranuronate-1′-yl) -5-fluorouracil 5a and 3-N-(β-D-glucopyranuronamide-1′-yl )-5-flurouracil 5_a′. All the synthesized compounds are new glycosides.The preliminary antitumor test showed that 4_b and 4_b′demonstrated excellent inhhitory effect on mice bearing S-180, with inhihitory rate of 78.8%(P<0.01>)and 57.3%(P<0. 01>)respectively.

Key words: Fluorouracil, Glycosidation, Antitumor drug, D-glucuronic acid, 5-Fluorouracil-N-glucuronide