Regioselective Synthesis of 2-Substituted-4-Methylbenzimidazole Nucleosides

Abstract

A series of 2-substituted-4-methylbenzimidazole nucleosides were synthesized with excellent stereo- and regioselectivity, and the unexpected regioselectivity is discussed. These compounds could be accessible on an industrial scale because they were obtained in good yields without chromatography.

Key words

nucleosides - regioselectivity - glycosylations - stereoselectivity - steric hindrance

References

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8

When chromatography was carried out on the intermediate product an unknown impurity was separated. The impurity we believed to be the complex of stannide and intermediate product was found to form in hot solvents or after standing for a long time in solvents open to air. When the impurity was subjected to deacylation the corresponding final product was obtained.