title: Synthesis of 3'-fluoro-2',3'-dideoxy-2',3'-didehydro-4'-ethynyl-D- and -L-furanosyl nucleosides.
abstract: An efficient procedure has been developed for the synthesis of 3'-fluoro-2',3'-dideoxy-2',3'-didehydro-4'-ethynyl D- and L-furanosyl nucleosides (1 and 2) starting from 2,3-O-isopropylidene-d-glyceraldehyde. The key intermediate 1-O-benzoyl-3E-fluoro-3,4-unsaturated-5,6-di(tert-butyldimethylsilyloxy)-2-hexanone 8 was obtained in nine steps with the overall yield of 22%. The alpha,beta-unsaturated ketone 8 was then treated with ethynylmagnesium bromide in a typical Grignard reaction procedure to afford the two intermediates 9 and 10, which after deprotection, oxidation, and acetylation gave the corresponding 4-ethynyl-substituted D- and L-sugar moieties 15 and 16, respectively. A series of D- and L-pyrimidine and purine nucleosides were prepared by the coupling of the sugar moieties with various silylprotected bases. The anomeric mixtures were obtained after condensation. After separation, the beta-isomers were further deprotected to yield the target nucleosides. All the newly synthesized 4'-substituted nucleosides were tested for their activities against HIV, among which the D-adenine derivative showed moderate anti-HIV activity (EC(50) = 25.1 microM) without significant cytotoxicity.
authors.affiliation: College of Pharmacy, The University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.forename: Wen
authors.initials: W
authors.lastname: Zhou
authors.forename: Raymond F
authors.initials: RF
authors.lastname: Schinazi
authors.forename: Chung K
authors.initials: CK
authors.lastname: Chu
mesh_terms: D019380:Anti-HIV Agents / Q000138:chemical synthesis*; D020650:Combinatorial Chemistry Techniques; D005663:Furans / Q000138:chemical synthesis*; D015394:Molecular Structure; D009705:Nucleosides / Q000138:chemical synthesis*; D013237:Stereoisomerism
chemical_list: D019380:Anti-HIV Agents; D005663:Furans; D009705:Nucleosides