反应详情

Other N-acyl derivatives of glucosamines of formula I (i.e. where both R1 and R2 are not a hydrogen atom) can be obtained by deacetylation of the respective derivatives of 1,3,4,6-tetra-O-D-glucosamine by means of alcoholic hydrochloric acid. See Examples 4, 7, and 8. The 1,3,4,6-tetra-O-acetyl-D-glucosamine (R1 =R2 =acetyl in formula II) reagent is synthesized from D-glucosamine by reaction of the latter with a protecting agent for the amino group (e.g. p-anisaldehyde) to form a Schiff's base. See Example 1(a) . The Schiff's base is then acetylated with acetic anhydride (Example 1(b)), then hydrolized with hydrochloric acid (Example 1(c)) and treated with sodium acetate (for example) to obtain 1,3,4,6-tetra-O-acetyl-D-glucosamine. Examples 1(d) and 2(a). The resultant 1,3,4,6-tetra-O-acetyl-D-glucosamine is condensed with the acylated amino acid or oligopeptide in the presence of DCC as described above.