Phenylethanoid glycosides structures

ISOLATION, STRUCTURE ELUCIDATION AND BIOACTIVITIES OF PHENYLETHANOID GLYCOSIDES FROM CISTANCHE, FORSYTHIA AND PLANTA GO PLANTS... 

We shall describe the isolation and structure elucidation and HPLC analysis of the phenylethanoid glycosides from several Cistanche plants growing in China, Mongoria, Kazakhstan, Pakistan, Turkey, Bahrain and Qatar, and from Forsythia plants and Plantago plants used as important herbal medicines. 

Five new phenylethanoid glycosides, tubuloside A-E (18-22) were isolated and their structures were elucidated, together with six known glycosides, acteoside (1), 2-acetylacteoside (2), isoacteoside (3), echinacoside (4), syringalide A 3 -a-L-rhamn oside (15), isosyringalide A 3 -a-L-rhamnoside (16), from C. tubulosa in Pakistan [18,19],... 

Structure elucidation of phenylethanoid glycosides from Ciatanche plants... 

Structure elucidation of phenylethanoid glycosides were carried out on the basis of spectral analysis and chemical evidences. Assignment of the 13C-NMR chemical shifts of phenylethanoid glycosides were re-examined and shown in Table 2. [24] Two dimensional NMR spectra, such as HfCOSY), H-... 

Phenylethanoid glycosides consist of phenyethyl glucosyl ether, acyl ester (couma-royl, feruroyl and caffeoyl) and glycosyl groups. The structure of isolated phenylethanoid glycosides was determined or identified by comparison with UV, IR, MS... 

C-NMR chemical shifts of isolated phenylethanoid glycosides were shown in Table 2. At present, two dimensional NMR spectra, such as - H COSY), 1H-13C(HMQC and HMBC) directly afford the importnat structural information Chemical shifts by methylation, glycosylation and acylation suggested the information of substituted carbon positions. 

Studies on the structure elucidation of phenylethanoid glycosides of °C-NMR, the change of chemical shift value were observed. 

In order to explain and confirm the biological activities claimed by the traditional medicine, and to search for new biologically active compounds we studied the antimicrobial, antioxidative, immunomodulatory, antiinflammatory, skin-regenerating and antiviral properties of Fraxinus ornus bark extract and its components. In a parallel detailed phytochemical investigation of the extract we isolated and determined the structures of many hydroxycoumarins, secoiridoid glucosides, caffeoyl esters of phenylethanoid glycosides, lignans and other phenolic compounds. 

It is known that the Oleaceae family is a rich source of phenylethanoid glycosides (PhGs). Many cinnamic esters of PhGs of diverse structures have been isolated from the genera Syringa, Forsythia, Ligistrum, Jasminum and Osmanthus [25]. However, only the occurrence of verbascoside (24) and calceolarioside A and B in Fraxinus species have been reported [19,26,27]. 

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