1-[2-Deoxy-3-O-[(1,1-dimethylethyl)dimethylsilyl]-β-D-erythro-pentofuranosyl]-3-(methylthio)-1H-pyrazolo[3,4-d]pyrimidin-4-amine

1-[2-Deoxy-3,5-bis-O-[(1,1-dimethylethyl)dimethylsilyl]-β-D-erythro-pentofuranosyl]-3-(methylthio)-1H-pyrazolo[3,4-d]pyrimidin-4-amine

1-[5-O-(Aminosulfonyl)-2-deoxy-3-O-[tris(1-methylethyl)silyl]-β-D-erythro-pentofuranosyl]-3-(ethylthio)-1H-pyrazolo[3,4-d]pyrimidin-4-amine

1-[2-Deoxy-3-O-[tris(1-methylethyl)silyl]-β-D-erythro-pentofuranosyl]-3-(ethylthio)-1H-pyrazolo[3,4-d]pyrimidin-4-amine

1-[2-Deoxy-3,5-bis-O-[tris(1-methylethyl)silyl]-β-D-erythro-pentofuranosyl]-3-(ethylthio)-1H-pyrazolo[3,4-d]pyrimidin-4-amine

1-(2-Deoxy-β-D-erythro-pentofuranosyl)-3-(ethylthio)-1H-pyrazolo[3,4-d]pyrimidin-4-amine

1-[2-Deoxy-3,5-bis-O-(4-methylbenzoyl)-β-D-erythro-pentofuranosyl]-3-(ethylthio)-1H-pyrazolo[3,4-d]pyrimidin-4-amine

4-Amino-1-[2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidine-3-acetonitrile

4-Amino-1-[5-O-[(1,1-dimethylethyl)dimethylsilyl]-2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidine-3-acetonitrile

3-(Cyclopropylthio)-1-[2,3-O-(1-methylethylidene)-5-O-[tris(1-methylethyl)silyl]-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidin-4-amine

3-[[(1R,2R)-2-[[(1,1-Dimethylethyl)dimethylsilyl]oxy]cyclopentyl]thio]-1-[2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidin-4-amine

1H-Pyrazolo[3,4-d]pyrimidine-3-methanol, 4-amino-1-[5-O-[(1,1-dimethylethyl)dimethylsilyl]-2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-, 3-methanesulfonate

3-[[(1S,2S)-2-[[(1,1-Dimethylethyl)dimethylsilyl]oxy]cyclopentyl]thio]-1-[2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidin-4-amine

(1R,2R)-2-[[4-Amino-1-[2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidin-3-yl]thio]cyclopentanol

(1S,2S)-2-[[4-Amino-1-[2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidin-3-yl]thio]cyclopentanol

1-[5-O-[(1,1-Dimethylethyl)dimethylsilyl]-2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-3-[[(1R,2R)-2-[[(1,1-dimethylethyl)dimethylsilyl]oxy]cyclopentyl]thio]-1H-pyrazolo[3,4-d]pyrimidin-4-amine

1-[5-O-[(1,1-Dimethylethyl)dimethylsilyl]-2,3-O-(1-methylethylidene)-β-D-ribofuranosyl]-3-[[(1S,2S)-2-[[(1,1-dimethylethyl)dimethylsilyl]oxy]cyclopentyl]thio]-1H-pyrazolo[3,4-d]pyrimidin-4-amine

(1R,2R)-2-[[4-Amino-1-[2,3-O-(1-methylethylidene)-5-O-[tris(1-methylethyl)silyl]-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidin-3-yl]thio]cyclopentanol

(1S,2S)-2-[[4-Amino-1-[2,3-O-(1-methylethylidene)-5-O-[tris(1-methylethyl)silyl]-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidin-3-yl]thio]cyclopentanol

(1R,2R)-2-[[4-Amino-1-[5-O-(aminosulfonyl)-β-D-ribofuranosyl]-1H-pyrazolo[3,4-d]pyrimidin-3-yl]thio]cyclopentanol