ChemInform Abstract: 1,2,5-ortho Esters of D-Arabinose as Versatile Arabinofuranosidic Building Blocks. Concise Synthesis of the Tetrasaccharidic Cap of the Lipoarabinomannan of Mycobacterium tuberculosis

1,2,5-ortho esters of D-arabinose were found to be ideally suited building blocks for the stereoselective formation of α and β arabinofuranosidic linkages after nucleophilic opening of the orthoester with oxygen and sulfur nucleophiles; the tetrasaccharidic cap of the lipoarabinomannan of Mycobacterium tuberculosis was then synthesized in a highly convergent manner.