(-)-(1'R,2'S,3'R)-1-(2,3-Dihydroxy-4-hydroxymethylcyclopent-1-enyl)-5-methyl-(1H,3H)-pyrimidine-2,4-dione (-)-(1R,2'S,3'R)-1-[2,3-Dihydroxy-4-hydroxymethyl-4-cylopenten-1-yl]thymine AIDS-114539 AIDS114539