Reaction #1596990

Reaction equation

Triacetate

5-Amino-7-thioxo-3-(2′,3′,5′-tri-O-acetyl-β-D-ribofuranosyl)-thiazolo[4,5-d]pyrimidin-2-one

→

89

Yield 60.1%

5-Amino-3-(2′,3′,5′-tri-O-acetyl-β-D-ribofuranosyl)-3H-thiazolo[4,5-d]pyrimidin-2-one

Yield 60.1%

Solvents

acetone

Conditions

Workup

1. 1
   Temperatureat refluxing for 1 h
2. 2
   Temperatureat reflux
3. 3
   workup.STIRRINGThe mixture was stirred for 5 min
4. 4
   OtherThe reaction was quenched
5. 5
   Otherby bubbling H2S (g) into the mixture for 2 h
6. 6
   FiltrationThe resulting mixture was filtered through a short pad of Celite®
7. 7
   Washwashed with EtOH
8. 8
   ConcentrationThe filtrate was concentrated
9. 9
   Otherpurified by flash column chromatography (silica, MeOH/CHCl3=1-2%)

Procedure

A suspension of Raney® 2800 nickel (3 big spatula, pre-washed with H2O, MeOH and acetone) in acetone (50 mL) was stirred at refluxing for 1 h. Triacetate 88 (0.93 g, 2.03 mmol) was subsequently added into the above suspension at reflux. The mixture was stirred for 5 min, cooled to room temperature over 30 min. The reaction was quenched by bubbling H2S (g) into the mixture for 2 h. The resulting mixture was filtered through a short pad of Celite® and washed with EtOH. The filtrate was concentrated and purified by flash column chromatography (silica, MeOH/CHCl3=1-2%) to afford 0.52 g (60%) of 89 as a white solid: mp 121-123° C.; 1H (400 MHz, d6-DMSO) δ 8.38 (s, 1H), 6.93 (s, 2H), 6.03 (d, J=3.6 Hz, 1H), 5.93 (dd, J=6.4, 3.6 Hz, 1H), 5.58 (t, J=6.0 Hz, 1H), 4.38 (dd, J=11.6, 3.6 Hz, 1H), 4.26 (m, 1H), 4.11 (q, J=6.0 Hz, 1H), 2.08 (s, 3H), 2.07 (s, 3H), 2.00 (s, 3H); MS (+)-ES [M+H]+ m/z 427.2. Elemental Analysis calc'd for C16H18N4O8S.0.5 CH3OH.0.25 H2O: C, 44.34; H, 4.62; N, 12.54; S 7.17. Found: C, 44.54; H, 4.88; N, 12.16; S, 7.17.

Source