반응 #351054

반응 방정식

NH3

2,5,6-Trichloro-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)benzimidazole

NH3

→

desired compound 44

2-Amino-5,6-dichloro-1-(β-D-ribofuranosyl)benzimidazole

용매

MeOH

반응 조건

후처리

1. 1
   기타to evaporate
2. 2
   기타the solution evaporated to dryness
3. 3
   기타absorbed onto silica gel (2 g)
4. 4
   기타chromatographed on a silica gel column
5. 5
   세척Elution of the column with CH2Cl2 :CH3OH (96:4)

실험 절차

2,5,6-Trichloro-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)benzimidazole (42, 0.48 g; 1 mmole) was dissolved in dry MeOH (10 ml). Liq. NH3 (10 ml) was added and the mixture heated in a steel bomb at 100° C. for 2 hr. This mixture was stirred at room temperature for 24 hr. Excess NH3 was allowed to evaporate and the solution evaporated to dryness, absorbed onto silica gel (2 g), and chromatographed on a silica gel column using silica gel (20 g; 60-200 mesh). Elution of the column with CH2Cl2 :CH3OH (96:4) gave the desired compound 44 as the major nucleoside. Evaporation of the solvent and crystallization of the residue from EtOH gave 44 (0.02 g; yield 6.06%). mp. 145° C.; UV Imax. (MeOH): 259 (7941) and 301 (8348) nm; Imax (pH1): 215 (26000) and 292 (7520) nm; Imax (pH11): 257 (7967) and 298 (7107) nm; 1H NMR(DMSO-d6): d 8.70 (s,1H, C7 -H, 8.28(s,1H, C4 -H), 7.90 (bs,2H, D2O exchangeable, NH2), 6.75(d,C1'H, J1,2 =4.5 Hz) and the rest of the sugar protons.

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