Several novel C-pseudonucleosides containing thiazolidin-4-one and phenyl connected by acetamide bond were rationally designed and easily synthesized at room temperature by using the unprotected sugar aldehyde as the starting material. The effects of the compounds on Con A-induced T cell proliferation were evaluated at five concentrations of 5, 10, 25, 50, and 100 mmol/L Interestingly,compounds 7a and 8a(n = 2, R = H) exhibited immunostimulating activities, while compounds 5a, 6a(n = 1, R = H) and 7b, 8b(n = 2, R = CH3) showed immunosuppressive activities. Another two compounds 5 b and 6b(n = 1, R = CH3) had no immunomodulating activities. These initial biological results suggested that subtle structural changes to the phenyl and acetamide bond of C-pseudonucleosides could have a significant effect on T cell proliferation bias, although it was difficult to formulate a rigorous structureactivity relationship based on the observed activities.
Sensors capable of recognizing cell surface carbohydrates,such as sialyl Lewis X(sLe^x),are invaluable research tools and for the diagnosis and early detection of many forms of cancer.In this paper,we report the design and synthesis of a series of bisboronic acids 6(a-f) as fluorescent sensors towards mono-/oligosaccharides.Among them,compounds 6d and 6e showed strong binding affinities with glucose and fructose,while compound 6c,in which two anthracene-based boronic acid units were linked by a hexamethylene spacer,was able to recognize sLe^x selectivity and stained HEPG2 cells at 1 μmoI/L.
Yan-En WangRui-Xue RongHua ChenMeng-Yuan ZhuBing-He WangXiao-Liu Li
