The syntheses of congeners of 1-deoxy-3-O-(α-D-glucopyranosyl)-mannojirimycin (1), a strong inhibitor of the glycoprotein-processing endo-mannosidase, are described. The chemical modifications of 1 involved all monodeoxy-genations and mono-O-methylations of the glucose unit and the replacement of this unit by D-galactose, D-xylose, and 2-chloro-2-deoxy-D-glucose. As reported previously, none of the modifications of 1, including deoxygenations and O- and N-methylations of the deoxymannojirimycin unit, improved the inhibitory properties, but demonstrated the high specificity in the recognition of 1 by the enzyme and allowed the assignment of intermolecular hydrogen bonds of the inhibitor • enzyme complex. Essential for complex formation were found NH-5, OH-2, OH-4, and OH-6 of the DMJ unit, as well as OH-3′, OH-4′, and CH2-6′ of the glucose unit. The residual activities on deoxygenating the OH-2′ and OH-6′ groups of 1 suggest their involvement at the periphery of the binding site.
描述了一种强烈抑制糖蛋白处理内切脱甲基酶的1-去氧-3-O-(α-D-葡萄糖吡喃基)-曼诺基霉素(1)同系物的合成。1的化学改性包括所有单去氧基化和单-O-甲基化葡萄糖单元以及将该单元替换为D-半乳糖、D-木糖和2-氯-2-脱氧-D-葡萄糖。正如先前报道的那样,1的所有改性,包括去氧化和去氧曼诺基霉素单元的O-和N-甲基化,都没有改善抑制性能,但表明了对酶识别1的高特异性,并允许分配抑制剂•酶复合物的分子间氢键。复合物形成所需的关键部位包括DMJ单元的NH-5、OH-2、OH-4和OH-6,以及葡萄糖单元的OH-3′、OH-4′和CH2-6′。对于1的OH-2′和OH-6′基团的去氧化残余活性表明它们参与了结合位点的外围。