2-Chloro-5,6-dibromo-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)benzimidazole → (2R,3R,4S,5R)-2-(5,6-dibromo-2-chloro-benzimidazol-1-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol

Participants

Reaction Steps

A solution of 569 mg (1 mmole) of (56) in 20 mL of NH3 /MeOH was stirred in a sealed flask at room temperature for 5 hr. Volatile materials were removed by evaporation. The residue was recrystallized from MeOH to give 337 mg (2 crops, 76%) of 57. Its 1H NMR spectrum was identical to that of (57) prepared by a direct bromination; see Method B.

Provenance & Evidence