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Eight new hydroperoxides and a new enone of germacrane-type sesquiterpenoids were isolated from the aerial parts of eight different samples of Eupatorium heterophyllum DC. (Asteraceae) collected in P.R. China. The structures were determined based on spectroscopic analyses. Seven of the eight samples produced hiyodorilactone A as a major constituent, while one afforded neither hiyodorilactone nor hydroperoxide. The results indicated the presence of diversity within this species.

Chemical constituents and evolutionally neutral DNA sequences of six samples of Cremanthodium lineare Maxim., collected in the Sichuan Province of China, were studied. Three samples produced furanoeremophilanes and the other three, eremophilan-8-ones. The chemotypes were found to be correlated with DNA sequence types, suggesting that the chemical diversity observed has a genetic origin. Production of furanoeremophilanes by a Cremanthodium species suggests an evolutionary relationship between Cremanthodium and Ligularia species, and possibly to related genera.

isolation and structure elucidation of 8 new hydroperoxyheterophyllin A—H (I)-(V) and one ketoheterophyllin A (VI)

Eight new hydroperoxides and a new enone of germacrane-type sesquiterpenoids were isolated from the aerial parts of eight different samples of Eupatorium heterophyllum DC. (Asteraceae) collected in P. R. China. The structures were determined based on spectroscopic analyses. Seven of the eight samples produced hiyodorilactone A as a major constituent, while one afforded neither hiyodorilactone nor hydroperoxide. The results indicated the presence of diversity within this species.

A thiophene, two furans, a dihydro furan, and two acetylenic benzene derivatives were isolated from the roots of Eupatorium heterophyllum collected in China. Structures were established on the basis of spectroscopic analyses as well as chemical transformations.

From Cremanthodium rhodocephalum (Asteraceae) collected in Yunnan Province of China, four bisabolane-type (three of them were new) and one oplopane-type sesquiterpenoids were isolated. Two new hydroperoxides were the first example with the bisabolane-type skeleton. This is the first report about the study on C. rhodocephalum.

A thiophene, two furans, a dihydro furan, and two acetylenic benzene derivatives were isolated from the roots of Eupatorium heterophyllum collected in China. Structures were established on the basis of spectroscopic analyses as well as chemical transformations.

We propose a novel figure-9 fiber laser using a frequency shifter to produce phase bias. Mode-locking operation is successfully archived, and arbitrary phase bias can be produced by changing the frequency shift.