Synthesis Of Troxerutin Amide-containing Derivatives Catalyzed By Lipase

Flavonoids are widely found in nature as secondary metabolites of plant, which featuringphysiological, pharmacological activity and low toxicity. Troxerutin, one of flavonoidsderivatives, has been proved showing therapeutic effect on varicose veins diseases and themodification of troxerutin has attracted considerable attention. In this thesis, thirty newtroxerutin derivatives have been synthesized though the enzymatic esterification reaction. Theall products were characterized by FT-IR,1H-NMR,13C-NMR, ESI-MS.Synthesis of troxerutin derivatives containing fatty amine (n-propylamine andisopropylamine) were catalyzed by lipase LS-10. The effects of various parameters such asenzyme origins, the concentration of enzyme, water content, different medium, and the molarratio of substrates were investigated. The highest conversion yields (58%) was achieved in thepresence of lipase LS-10(20mg/mL), the molar ratio of substrates5:1(amine tovinylglutaryl-troxerutin) at50oC in pyridine (water content≤1%) for24h.Troxerutin derivatives containing N-heterocyclic amines (piperazine, methylpiperazine,piperdine, and morpholine) were synthesized through enzymatic reaction. Among the tenkinds of commercially available enzymes tested, lipase LS-10produced the highest yield.Investigation of water content and different medium constituted by pyridine, DMF, andDMSO showed that pyridine containing water lower than2%was the efficient medium.Increasing of the molar ratio of morpholine to vinylglutaryl-troxerutin to6:1produced thehighest yield. The carbon chain length of vinyl-troxerutin esters did not show significanteffect and the highest (51%) yields reached plateau after reaction at50oC for24h.The enzymatic synthesis of troxerutin derivatives containing triazine were investigatedby using ultrasound irradiation and ordinary shaking. The results showed that ultrasoundirradiation could increase the activity of lipase G Amano50and the higher yield (56%) wasreached in the ultrasound irradiation (45KHz,200W) compared with that (39.3%) of theshaking.