Synthesis and immunostimulating activity of C-pseudonucleosides containing N-phenyl thiazolidin-4-one

Several novel C-pseudonucleosides containing N-phenyl thiazolidin-4-one were synthesized at room temperature 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 μM. Some compounds, such as 5d, 5e, 5f, and 4g could significantly increase the proliferation by 62, 63, 70, and 53 % at low concentration of 5 μM, respectively. The structure–activity relationship indicated that the lipophilicity substituents like chloro atom, methyl, and methoxyl on the para position of N-3 phenyl at the thiazolidin-4-one ring had a detrimental impact on the T cell proliferation. The C-2 configuration and the electronic property of the lipophilicity substituents likely had slight effects on the immunostimulatory activities of such C-pseudonucleosides.