Quinolone nucleosides:: 6,7-dihalo-N-β- and α-glycosyl-1,4-dihydro-4-oxo-quinoline-3-carboxylic acids and derivatives.: Synthesis, antimicrobial and antiviral activity

Reaction of the silylated 6,7-dihaloquinoline bases 10-12 with 1-O-acetyl-2,3,5-tri-O-benzoyl-beta-D-ribofuranose (13) gave ethyl 7-chloro-6-flouro-1,4-dihydro-4-oxo-1-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)quinoline-3-carboxylate (14) and the free acids 15 and 16, respectively, which led on deblocking of the sugar moiety to the free nucleosides 17, 18 and 20, respectively. Treatment of 14 with methanolic ammonia afforded the amide derivative 19. Ribosylation of 11 with 1,2-di-O-acetyl-3-azido-3-deoxy-5-p-toluoyl-beta-D-ribofuranose (21) afforded the azido nucleoside 22, which was again converted into the free nucleoside 23. Analogously, reaction of 11 with the chloro deoxyribose derivative 24 led to a mixture of alpha / beta (2:1) anomers of 25. Deblocking and recrystallization of the product gave mainly the alpha-anomer 26. Compounds 17-19, 23 and 26 were evaluated against Escherichia coli and found inactive. Compound 16-18 and 22 were inactive aganist HIV-1 (III B) and HIV-2 (ROD) induced cytopathicity in human MT-4 lymphocyte cells.