139
Fig. 62 Aromatic compounds (1)
in the purification of the eremophilanes dehydrofukinone (5), 20, 23, 340, 341, 342,
and 358 and the triterpenoids 846, 853, 854, 856, 857, 858, and 859 [41]. The structure of 23 was identified by comparison with a synthetic compound reported prior
to our research [297]. The configuration of an epoxide is sometimes not easy to
elucidate due to its nearly planar local shape, so chemical synthesis helped to determine the structure. There is another similar example given by compound 22 (Sect.
3.24). Five compounds (88, 89, 1022, 1023, and 1045) were isolated from sample 4
(aerial parts) [84]. It is interesting to note that both plucheoside D1 (1022) [CD: [θ]
–6600°cm
2
mol
−1
(287 nm)] and tortoside F (1023) [CD: [θ] +7700°cm
2
mol
−1
(284 nm)] were isolated, since their aglycones are enantiomers of one another.
Chemical Constituents of Ligularia Species (Asteraceae) and Their Diversity…
Fig. 62 Aromatic compounds (1)
in the purification of the eremophilanes dehydrofukinone (5), 20, 23, 340, 341, 342,
and 358 and the triterpenoids 846, 853, 854, 856, 857, 858, and 859 [41]. The structure of 23 was identified by comparison with a synthetic compound reported prior
to our research [297]. The configuration of an epoxide is sometimes not easy to
elucidate due to its nearly planar local shape, so chemical synthesis helped to determine the structure. There is another similar example given by compound 22 (Sect.
3.24). Five compounds (88, 89, 1022, 1023, and 1045) were isolated from sample 4
(aerial parts) [84]. It is interesting to note that both plucheoside D1 (1022) [CD: [θ]
–6600°cm
2
mol
−1
(287 nm)] and tortoside F (1023) [CD: [θ] +7700°cm
2
mol
−1
(284 nm)] were isolated, since their aglycones are enantiomers of one another.
Chemical Constituents of Ligularia Species (Asteraceae) and Their Diversity…