Dienophile‐Modified Mannosamine Derivatives for Metabolic Labeling of Sialic Acids: A Comparative Study

摘要: Sialic acids play an important role in numerous cell adhesion processes, and sialylation levels are known to be altered under certain pathogenic conditions, such as cancer. Metabolic glycoengineering with mannosamine derivatives is a convenient way introduce non-natural chemical reporter groups into sialylated glycoconjugates, offering the opportunity label sialic by using bioorthogonal ligation chemistry. The labeling intensity depends not only on rate of reaction but also extent which natural replaced modified ones; that is, incorporation efficiency. Here, we present comparative study eight featuring terminal alkenes can labeled inverse-electron-demand Diels-Alder (DAinv) reaction. differed chain length well type linkage (carbamates, amides, urea) connects alkene sugar. As general trend, increasing lengths resulted higher DAinv reactivity and, at same time, reduced Carbamates were better accepted than amides length; nevertheless, latter more intense cell-surface staining, visible live-cell fluorescence microscopy. A urea derivative was shown accepted.