Urea Glycoside Synthesis in Water

Abstract

A novel approach to the synthesis of urea glycosides in aqueous media has been developed. Reaction of Steyermark’s ­glucosyl carbamate 1 with amines was carried out in water to afford urea glucosides in good yields. This method was successfully ­applied to develop a new route to the synthesis of urea-tethered neoglycoconjugates and pseudooligosaccharides.

Key words

carbohydrates - glycosylations - glycosides

References

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9

The separation of glucose, hydrolyzed product of 1, by ODS column was difficult in this case.

12

Spectroscopic data of 5: ¹H NMR (400 MHz, CD₃OD): δ = 2.77 (2 H, t, J = 7.0 Hz), 3.13 (1 H, t, J = 9.0 Hz), 3.25 (1 H, t, J = 9.0 Hz), 3.32 (1 H, ddd, J = 9.0, 5.5 and 2.0 Hz), 3.37 (2 H, t, J = 7.0 Hz), 3.38 (1 H, t, J = 9.0 Hz), 3.63 (1 H, dd, J = 12.0 and 5.5 Hz), 3.81 (1 H, dd, J = 12.0 and 2.0 Hz), 4.73 (1 H, dd, J = 9.0 Hz), 7.15-7.29 (5 H). ¹³C NMR (100 MHz, CD₃OD): δ = 37.3, 42.6, 62.8, 71.6, 74.3, 79.1, 79.2, 82.8, 127.3, 129.5, 129.8, 140.7, 160.5.