抄録
A new procedure for the synthesis of 3'-fluorocarbocyclic oxetanocin A (1b) was developed. Addition of iodine fluoride to O-cyclohexylidene-cis-2-hydroxymethyl-3-methylene-1-cyclobutanol (4) afforded O-cyclohexylidene-(1S*, 2S*, 3R*)-3-fluoro-3-iodomethyl-2-hydroxymethyl-1-cyclobutanol (5) and the undesired (1S*, 2S*, 3S*)-isomer (6) in 6.2% and 38% yields, respectively. When fluorine was introduced into the carbocycle after condensation of 6-chloropurine, 6-chloro-9-[(1R*, 2S*, 3R*)-3-fluoro-3-iodomethyl-2-(trityloxymethyl)cyclobutyl]purine (10) was obtained as a sole addition product, which was readily converted to 1b. This compound (1b) exhibited a broad spectrum of antiviral activity, especially against human cytomegalovirus.
