A novel class of 3-demethoxy-3-glycosylaminothiocolchicines (7) was prepared and tested for muscle relaxantactivity. The syntheses were performed starting from the new 3-amino-3-demethoxythiocolchicine (5) preparedin good yield from 3-O-demethylthiocolchicine (1c) using the Buchwald−Hartwig reaction. The condensationof 5 with a series of pentose and hexose sugars (6) gave a series of 3-demethoxy-3-glycosylaminothiocolchicines (7). Their preparation was accomplished by adapting and improving a previous procedure forthe preparation of N-arylglycosylamines. In particular, replacing traditional heating with microwave irradiationrepresents the key improvement of the process. The biological activity of the 3-demethoxy-3-glycosylaminothiocolchicines (7) was evaluated on GABA and strychnine-sensitive glycine receptors present in ratbrain and spinal cord.
