Reaction #6882

Reaction equation

hydrochloric acid

sodium hydroxide

nucleoside

1-(3,5-di-O-benzyl-2,6-di-O-(p-toluenesulphonyl)-β-D-allofuranosyl)thymine

→

nucleoside

(1S,4R,5R,7R,8R)-4,8-Dibenzyloxy-7-(thymin-1-yl)-2,6-dioxabicyclo[3.2.1]octane

Solvents

ethanol

H2O

Conditions

Workup

1. 1
   TemperatureThe resulting mixture was heated
2. 2
   Temperatureunder reflux for 16 h
3. 3
   ExtractionThe volume of the mixture was reduced to 50% and extraction
4. 4
   DryingThe combined organic phase was dried (Na 2SO4)
5. 5
   Otherevaporated to dryness under reduced pressure
6. 6
   OtherThe residue was purified by silica gel column chromatography

Procedure

To a stirred solution of nucleoside 17 (0.63 g, 0.81 mmol) in a mixture of ethanol and H2O (40 cm3, 1:1, v/v) at room temperature was added an aqueous solution of sodium hydroxide (1M, 7 cm3). The resulting mixture was heated under reflux for 16 h and then neutralised by addition of dilute hydrochloric acid (10 cm3). The volume of the mixture was reduced to 50% and extraction was performed using dichloromethane (50 cm3×3). The combined organic phase was dried (Na 2SO4) and evaporated to dryness under reduced pressure. The residue was purified by silica gel column chromatography using dichloromethane/methanol (99:1,v/v) as eluent to give nucleoside 18 as a white solid material (0.40 g, 93%) after evaporation of the solvents under reduced pressure.

Source