Abstract
In the course of the investigation of biologically active substances from the rare plants, we isolated seven novel sesquiterpenoids, named euonymusins A〜G (1〜7) from the fruilts of the rare plant Euonymus chibae. Their absolute stereostructures were established by a combination of Mass, IR, 2D-NMR and CD spectra, and chemical reactions such as alkaline hydrolysis. The cytotoxic activities of compounds 1〜7 against three cancer cell lines (RERF-LC-KJ: lung cancer; HeLa:cervical cancer; and HSC-2:oral cancer) were examined. Compounds 5 and 6 selectively showed the strong cytotoxic activities against RERF-LC-KJ. A large amount of pigment (8) was isolated from the leaves of E. chibae. Compound 8 was identified as methyl phaeophoride a by FAB-Mass, IR, UV, and NMR spectra. It was possible to assign all carbon signals of compound 8 by measurement of 2D-INADEQUATE in pyridine-d_5.
