A Novel Type of Dimeric Secoiridoid Glycoside from Lisianthius jefensis R OBYNS et E LIAS

A dimeric secoiridoid glucoside named lisianthioside ( l ) has been isolated from the roots of Lisianthius jefensis R OBYNS et E LIAS (Gentianaceae). The structure was established by spectroscopic analysis (UV, IR, 1 H‐ and 13 C‐NMR, DCI‐MS) of glycoside 1 , peracetate 1a , aglycone 3 and the dimethoxy derivatives 4a – c . Lisianthioside ( 1 ) is the first representative of a novel type of dimeric secoiridoids. Biogenetically derived from two sweroside ( 2 ) moieties, the tricyclic aglycone features a symmetrical 12‐membered bislactone ring. In contrast to the moderately bitter sweroside ( 2 ), lisianthioside ( 1 ) is tasteless.