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An HPLC-UV-MS method for simultaneous identification of predominant phenolics and minor nucleoside derivatives in<i> Gastrodia elata</i> was developed, which was based on their UV and MS characteristics summarized through a series of homemade reference standard experiments. Phenolics showed characteristic UV λ<sub>max</sub> at 267 nm, [M + NH₄]⁺ base peak in positive mode and [M-H]⁻ base peak in negative mode while nucleosides exhibited UV λ<sub>max</sub> at 255 nm, [M + H]⁺, [M-H + 2H₂O]⁻ or [M-H + CH₃COOH]⁻. Phenolics conjugates mainly underwent the consecutive loss of gastrodin residue (-268 U) and the combined loss of H₂O and CO<sub>2 </sub>from the citric acid unit under negative MS/MS conditions whereas nucleosides simply lost the ribose (-132 U) under positive MS/MS conditions. According to these characteristics, a special pattern under MS/MS conditions and reported compound data for<i> G. elata</i> in the literature, not only 15 phenolics were identified but also 6 nucleoside derivatives were identified. Among these compounds, seven phenolics and three nucleoside derivatives have not been reported yet from<i> G. elata</i>.
A new xanthone glycoside ( 1 ) has been isolated from Swertia franchetiana together with five known xanthone glycosides. Their structures were elucidated as 7- O -[β- d -xylopyranosyl-(1→2)-β- d -xylopyranosyl]-1,7,8-trihydroxy-3-methoxyxanthone ( 1 ), 7- O -[α- l -rhamnopyranosyl-(1→2)-β- d -xylopyranosyl]-1,7,8-trihydroxy-3-methoxyxanthone ( 2 ), 8- O- β- d -glucopyranosyl-1,3,5,8-tetrahydroxyxanthone ( 3 ), 1- O- β- d -glucopyranosyl-1-hydroxy-3,7,8-trimethoxyxanthone ( 4 ), 1- O -[β- d -xylopyranosyl-(1→6)-β- d -glucopyranosyl]-1-hydroxy-2,3,5-trimethoxyxanthone ( 5 ) and 1- O -[β- d -xylopyranosyl-(1→6)-β- d -glucopyranosyl]-1-hydroxy-3,5-dimethoxyxanthone ( 6 ) on the basis of spectroscopic evidence.