(3R,4'S)-5-acetoxy-2-N-methyl-3-(2,2-dimethyl-1,3-dioxolan-4-yl)-1,2-isoxazolidine

(3'R,4''S,5'S)-1-[2-N-methyl-3-(2,2-dimethyl-1,3-dioxolan-4-yl)-1,2-isoxazolidinyl]thymine

1-[(3R,5S)-3-((S)-1,2-Dihydroxy-ethyl)-2-methyl-isoxazolidin-5-yl]-5-methyl-1H-pyrimidine-2,4-dione