Synthesis of 4,6-dideoxy-3-fluoro-2-keto-β- d-glucopyranosyl analogues of 5-fluorouracil, N 6-benzoyl adenine, uracil, thymine, N 4-benzoyl cytosine and evaluation of their antitumor activities (original) (raw)

2010, Bioorganic Chemistry

The synthesis of the unsaturated 4,6-dideoxy-3-fluoro-2-keto-β-d-glucopyranosyl nucleosides of 5-fluorouracil (6a), N6-benzoyl adenine (6b), uracil (6c), thymine (6d) and N4-benzoyl cytosine (6e), is described. Monoiodination of compounds 1a,b, followed by acetylation, catalytic hydrogenation and finally regioselective 2′-O-deacylation afforded the partially acetylated dideoxynucleoside analogues of 5-fluorouracil (5a) and N6-benzoyl adenine (5b), respectively. Direct oxidation of the free hydroxyl group at the 2′-position of 5a,b, with simultaneous elimination reaction of the β-acetoxyl group, afforded the desired unsaturated 4,6-dideoxy-3-fluoro-2-keto-β-d-glucopyranosyl derivatives 6a,b. Compounds 1c–e were used as starting materials for the synthesis of the dideoxy unsaturated carbonyl nucleosides of uracil (6c), thymine (6d) and N4-benzoyl cytosine (6e). Similarly a protection-selective deprotection sequence followed by oxidation of the free hydroxyl group at the 2′-position of the dideoxy benzoylated analogues 9c–e with simultaneous elimination reaction of the β-benzoyl group, gave the desired nucleosides 6c–e. None of the compounds was inhibitory to a broad spectrum of DNA and RNA viruses at subtoxic concentrations. The 5-fluorouracil derivative 6a was more cytostatic (50% inhibitory concentration ranging between 0.2 and 12 μM) than the other compounds.The synthesis of the unsaturated 4,6-dideoxy-3-fluoro-2-keto-β-d-glucopyranosyl nucleosides of 5-fluorouracil (6a), N6-benzoyl adenine (6b), uracil (6c), thymine (6d) and N4-benzoyl cytosine (6e), is described. The newly synthesized 2′-ketopyranosyl derivatives were not potent antivirals at subtoxic concentrations. The 5-fluorouracil derivative 6a was more cytostatic (50% inhibitory concentration ranging between 0.2 and 12 μM) than the other compounds.