Synthetic Study Of Strictosidine And Its Derivatives Based On Biomimetic Strategy

Monoterpenoid indole alkaloids are large class compounds with diverse biological activity. They derived from common biosynthetic precursor strictosidine. Most biomimetic synthesis of monoterpenoid indole alkaloids uses tryptamine and secologanin as starting material. They condensed together to form strictosidine and vincoside at biomimetic condition. The extract of leaves of Weigela florida was used as secologanin source to react with tryptamine in the biomimetic conditions. The strictosidine was obtained after isolation of the reaction solution and characterization by MS and NMR methods. The strictosidine was treated with almond powder at pH buffer to hydrolyze the glycoside. The aglycone and some rearrangement products were obtained and identified by mass spectrum. When the extract of leaves reacted with tryptamine in methanol, the cyclized product strictosamide was obtained.When5-fluorotryptamine was used to replace tryptamine to react with the extract of leaves, fluorostrictosidine and fluorostrictosamide were obtained. These two derivatives are very important intermediates to prepare other derivatives of monoterpenoid indole alkaloids and will lead a new type fluoro-containing monoterpenoid indole alkaloids.Weigela florida is perennial shrub which belong to Caprifoliaceae family, planted as a common ornamental plant. There is little study of its chemical composition. In the experimental process of this work, one compound was separated from the extract of leaves of Weigela florida. The structure of the compound was determined by mass spectrometry,1H NMR and IR spectroscopy.