Two Novel Guaiane Sesquiterpenes from the Whole Plant of Youngia japonica

Abstract

Two new guaiane-type sesquiterpenes (1 and 2) together with eight related sesquiterpenoidal constituents (3-10) were isolated from the whole extract of Youngia japonica. The chemical structures of 1-10 were established by spectroscopic analyses as 4-epi-isolipidiol (1), 4′-p-hydroxyphenylacetyl crepiside E (2), isolipidiol (3), isoambeboin (4), grosheimin (5), annuionone D (6), loliolide (7), youngiajaponicoside A (8), crepiside H (9), and crepiside E (10), respectively. Among the isolated components, 5 exhibited a significant inhibitory effect on the proliferation of cultured human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15).

Antimicrobial and Cytotoxic Activities of Selected Hieracium L. s. str. (Asteraceae) Extracts and Isolated Sesquiterpene Lactones

“…The cytotoxic effect of crepiside E was also investigated by other authors on SK‐MEL‐2 (human melanoma), SK‐OV‐3 (human ovary adenocarcinoma), HCT15 (human colorectal adenocarcinoma) and A549 cells (concentrations up to 12.7 μg/mL), [47] as well as on L1210 (mouse lymphocytic leukemia) cells (concentrations up to 5.0 μg/mL), [48] but in tested concentrations the compound did not achieve 50 % inhibition of the growth of these cells. On the other hand, desacylcynaropicrin, which is the crepiside E aglycone, was shown to be a potent cytotoxic agent for HeLa ( IC 50 =1.4 μg/mL), [49] SK‐MEL‐2 ( IC 50 =3.6 μg/mL), XF498 (human glioblastoma, IC 50 =3.9 μg/mL), HCT15 ( IC 50 =6.0 μg/mL), SK‐OV‐3 ( IC 50 =11.9 μg/mL) and A549 cells ( IC 50 =13.3 μg/mL) [50] .…”