1,2,3,5-Tetraacetyl-beta-D-ribofuranose → 2-Amino-5,6-dichloro-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)benzimidazole

HRID 727015

Reaction equation

HRID 727015 reaction equation
[NH2:1][C:2]1[NH:3][C:4]2[CH:10]=[C:9]([Cl:11])[C:8]([Cl:12])=[CH:7][C:5]=2[N:6]=1.C(O[C@@H:17]1[O:29][C@H:28]([CH2:30][O:31][C:32](=[O:34])[CH3:33])[C@@H:23]([O:24][C:25](=[O:27])[CH3:26])[C@H:18]1[O:19][C:20](=[O:22])[CH3:21])(=O)C.[Si](S(C(F)(F)F)(=O)=O)(C)(C)C>C(#N)C>[NH2:1][C:2]1[N:3]([C@@H:17]2[O:29][C@H:28]([CH2:30][O:31][C:32](=[O:34])[CH3:33])[C@@H:23]([O:24][C:25](=[O:27])[CH3:26])[C@H:18]2[O:19][C:20](=[O:22])[CH3:21])[C:4]2[CH:10]=[C:9]([Cl:11])[C:8]([Cl:12])=[CH:7][C:5]=2[N:6]=1

Participants

5

Conditions

Temperature
60 °C

Procedure

2-Amino-5,6-dichlorobenzimidazole (4) (3 g, 16 mmole) was dissolved in dry acetonitrile (150 ml) and stirred in an inert atmosphere at 60° C. BSA (4.37 ml, 17 mmole) was added and the mixture was stirred for 10 minutes. 1,2,3,5-tetra-O-acetyl-β-D-ribofuranose (5.09 g, 16 mmole) and TMSTf (3.29 ml, 17 mmole) were added to the clear solution and the mixture was allowed to stir at 60° C. for 1 hr. The mixture was concentrated under reduced pressure and separated on a silica column to yield 1.14 g (15%) of 2-amino-5,6-dichloro-1-(2,3,5,tri-O-acetyl-β-D-ribofuranosyl) benzimidazole (43). 13C NMR (CDCl3): d 170.04 ppm, 169.56, 169.11, 154.57, 141.64, 132.53, 125.90, 1123.45, 117.72, 109.49, 85.78, 80.99, 70.95, 69.83, 62.91, 20.74, 20.54, 20.20. 1H NMR (CDCl3): d 0.96 ppm (s, 3H), 1.09 (s, 3H), 1.13 (s, 3H), 3.75 (m, 2H), 4.08 (dd, 1H), 5.00 (dd, 1H), 5.13 (t, 1H), 5.42 (s, 2H), 5.61 (d, 1H), 7.27 (s, 1H), 7.42 (s, 1H). MS (FAB) m/e 758,718, 676, 460, 426, 259, 217, 139.

Workup

  1. additionBSA (4.37 ml, 17 mmole) was added
  2. stirringthe mixture was stirred for 10 minutes
  3. stirringto stir at 60° C. for 1 hr
  4. concentrationThe mixture was concentrated under reduced pressure
  5. customseparated on a silica column

Sources & evidence

ORD record
ord-14c6da77682c4dbd9ad22c6c59fa8c6e
Source dataset
uspto-grants-1998_01
Patent number
US05712255

Linked notes

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