Some further studies on the synthesis of glycopeptide derivatives: 2-acetamido-2-deoxy-beta-D-glucopyranosylamine derivatives.

1. The isolation, characterization and properties of two by-products in the preparation of 2-acetamido-3,4,6-tri-O- acetyl-2-deoxy-beta-d-glucopyranosylamine are described. They are bis(2-acetamido-2-deoxy-d-glucopyranosyl)amines. 2. An independent synthesis of the bis-glycopyranosylamines is reported and conditions are given for their preparation in high yield. 3. Further improvements are given for the synthesis of 2-acetamido-1-N-(beta-l- aspartyl)-2-deoxy-beta-d-glucopyranosylamine and the alpha-l-aspartyl isomer. 4. The synthesis of 2-acetamido-1-N-acetyl-2-deoxy-beta-d-glucopyranosylamine is described.