197
(629), euparin (952), and its derivatives 947, 949, and 954 [38, 40, 150].
Among these compounds, subspicatins (1-angeloyloxyfuranoeremophilanes
and -eremophilan- 12,8-olides) are characteristic compounds of L. subspicata
(Sect. 3.27). From three hybrid samples between L. tongolensis and L. cymbulifera
(samples 8–10), furanoeremophilanes 161, 191, 203, 204, 208, 224, and 225 were
found [128]. These two species are close to each other in their chemical composition except that tetradymol (225) is the major characteristic component of L. cymbulifera (Sects. 3.25 and 3.34). From three hybrid samples 11–13 between
L. nelumbifolia and L. subspicata, three furanoeremophilanes (161, 171, and 225)
and a sinapyl alcohol derivative (989) (nelumol A) were obtained [127]. Compounds
171 and 989 may originate from L. subspicata and from L. nelumbifolia, respectively. From sample 14, a hybrid between L. duciformis and L. cyathiceps, the
eremophilanes 1, 289, 293, 306, 308, and 316 and the aromatic compounds 979,
987, and 989 as well as squalene (886) were isolated [18]. Of these, the aromatic
compounds might originate from L. duciformis and the eremophilanes from
L. cyathiceps, respectively. From sample 15, a hybrid between L. duciformis and
L. yunnanensis, both aromatic compounds (933 and 980) and lupeol (828), were
obtained. This sample did not produce eremophilanes, because both of the parent
species do not produce this class of sesquiterpenoids [18].
Finally, in addition to the Ligularia hybrid mentioned above, two samples of
intergenic hybrids between L. nelumbifolia and Cremanthodium stenoglossum
(samples 16 and 17) were analyzed, leading to the purification of two eremophilanes,
namely, eremophila-9,11-dien-8-one (2) and petasin (54) [33]. The genus
Cremanthodium is close to Ligularia taxonomically [3, 296].
3.38 Further Ligularia Species I: altaica de Candolle,
L. dolichobotrys Diels, L. franchetiana (H. Léveillé)
Handel-Mazzetti, L. persica Boissier, L. speciosa Fischer
et Meyer, and L. thyrsoidea (Ledebour) de Candolle
The following are the results obtained for several other Ligularia specimens, with
information on the phytochemical analysis of 31 samples of 29 Ligularia species
summarized below.
In 2010, Wang et al. reported on the isolation of altaicalarins A–D (719, 718,
656, and 661) and two bisabolane derivatives (653 and 699) as well as a hydrocarbon (647) from L. altaica de Candolle (sample 1 from the Xinjiang Autonomous
Region, China) (Table 46) [223]. Altaicalarins A and B (719 and 718) are aromatized derivatives each bearing a bisabolane skeleton. This is the only published
report on L. altaica.
Ligularia dolichobotrys Diels (sample 2 from Shaanxi Province) produced four
10H-furanoeremophilanes (375, 490 (the major constituent), 493, and 509), three
bakkanes (629 (bakkenolide A), 630, and 631), two triterpenes (845 (friedelin) and
848 (ursolic acid)), and four additional compounds (125, 787, 788, and 897) [101,
Chemical Constituents of Ligularia Species (Asteraceae) and Their Diversity…
(629), euparin (952), and its derivatives 947, 949, and 954 [38, 40, 150].
Among these compounds, subspicatins (1-angeloyloxyfuranoeremophilanes
and -eremophilan- 12,8-olides) are characteristic compounds of L. subspicata
(Sect. 3.27). From three hybrid samples between L. tongolensis and L. cymbulifera
(samples 8–10), furanoeremophilanes 161, 191, 203, 204, 208, 224, and 225 were
found [128]. These two species are close to each other in their chemical composition except that tetradymol (225) is the major characteristic component of L. cymbulifera (Sects. 3.25 and 3.34). From three hybrid samples 11–13 between
L. nelumbifolia and L. subspicata, three furanoeremophilanes (161, 171, and 225)
and a sinapyl alcohol derivative (989) (nelumol A) were obtained [127]. Compounds
171 and 989 may originate from L. subspicata and from L. nelumbifolia, respectively. From sample 14, a hybrid between L. duciformis and L. cyathiceps, the
eremophilanes 1, 289, 293, 306, 308, and 316 and the aromatic compounds 979,
987, and 989 as well as squalene (886) were isolated [18]. Of these, the aromatic
compounds might originate from L. duciformis and the eremophilanes from
L. cyathiceps, respectively. From sample 15, a hybrid between L. duciformis and
L. yunnanensis, both aromatic compounds (933 and 980) and lupeol (828), were
obtained. This sample did not produce eremophilanes, because both of the parent
species do not produce this class of sesquiterpenoids [18].
Finally, in addition to the Ligularia hybrid mentioned above, two samples of
intergenic hybrids between L. nelumbifolia and Cremanthodium stenoglossum
(samples 16 and 17) were analyzed, leading to the purification of two eremophilanes,
namely, eremophila-9,11-dien-8-one (2) and petasin (54) [33]. The genus
Cremanthodium is close to Ligularia taxonomically [3, 296].
3.38 Further Ligularia Species I: altaica de Candolle,
L. dolichobotrys Diels, L. franchetiana (H. Léveillé)
Handel-Mazzetti, L. persica Boissier, L. speciosa Fischer
et Meyer, and L. thyrsoidea (Ledebour) de Candolle
The following are the results obtained for several other Ligularia specimens, with
information on the phytochemical analysis of 31 samples of 29 Ligularia species
summarized below.
In 2010, Wang et al. reported on the isolation of altaicalarins A–D (719, 718,
656, and 661) and two bisabolane derivatives (653 and 699) as well as a hydrocarbon (647) from L. altaica de Candolle (sample 1 from the Xinjiang Autonomous
Region, China) (Table 46) [223]. Altaicalarins A and B (719 and 718) are aromatized derivatives each bearing a bisabolane skeleton. This is the only published
report on L. altaica.
Ligularia dolichobotrys Diels (sample 2 from Shaanxi Province) produced four
10H-furanoeremophilanes (375, 490 (the major constituent), 493, and 509), three
bakkanes (629 (bakkenolide A), 630, and 631), two triterpenes (845 (friedelin) and
848 (ursolic acid)), and four additional compounds (125, 787, 788, and 897) [101,
Chemical Constituents of Ligularia Species (Asteraceae) and Their Diversity…