Five known and one new sesquiterpene lactones were isolated from fresh chicory roots (Cichorium intybus). The new compound 11 (S), 13-dihydrolactucopicrin was identified by UV, NMR, 13C NMR, and mass spectroscopy. The extraction procedure and HPLC analysis of sesquiterpene lactones in chicory were improved. The bitterness detection thresholds of all compounds were individually determined by triangle testing. 11 (S), 13-Dihydrolactucopicrin was extremely bitter, with a threshold level of 0.2 ppm. Four other lactones showed threshold values similar to that of quinine hydrochloride.Chicory (Cichorium intybus) roots are inevitably produced by the cultivation and production of the edible chicory leaves. At present they are a waste. As the roots contain both the valuable fructose polymer inulin and some bitter sesquiterpene lactones, a research project of the Department of Food Science of Wageningen Agricultural University in the past years has been to explore possible uses of the otherwise useless roots. One possi-
The =C N M R spectra of a number of partial derodane structures and adogous compoonds were recorded.The infomation thus obtained enabled the assignment of the "CNMR shifts in a number of naturally occurring derodanes.
During the large-scale synthesis of an O-cinnamoyltaxicin I acetonide, an intermediate for the semisynthesis of 7-deoxypaclitaxel derivatives, side-product 3 was formed via a vinylogous retro-aldol reaction and a long-range hydride shift from O-cinnamoyltaxicin I (1) under alkaline reaction conditions. Compound 3 has two hemi-acetal bridges at C-1,C-9 and C-10,C-13. Compound 4 was formed from side-product 3 under acidic reaction conditions and is the first C-13 spiro-taxane described in the literature. This spiro-taxane has two acetal bridges between C-1, C-13 and C-10,C-13.
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