反应详情

1-(β-D-glucopyranosyl)-3-n-propylurea (1.50 g) was dissolved in a mixture of water (10 ml) and acetic acid (2 ml), and to the resulting solution was added 560 mg (1.5 mol. equivalents) of sodium nitrite at ambient temperature under stirring to effect the nitrosation. The reaction mixture was treated with Amberlite IR-120 (H+ form) for the removal of sodium ion and then concentrated to dryness below 35° C. and under a reduced pressure. Crystallisation of the residue from n-propanol gave 1.35 g of the titled compound. Yield 80%. mp. 112° C. (decomposition with foaming). [α]D21 -6° (c 1.0, H2O).

1. concentrationconcentrated to dryness below 35° C. and under a reduced pressure
2. customCrystallisation of the residue from n-propanol