172
analysis [29]. Among them, the chemical compositions of types 1–5 were somewhat
consistent. From samples of these types (samples 1–3 and 5–7), furanoeremophilanes
160, 161, 168, 189, 192, 212, 216, 232, and 247 were isolated, as well as the nonfurano compound 5. From a type 6 sample (sample 8), furanoeremophil-1(10)-ene
derivatives (256, 288, and 291) were obtained. Later, we found two more Ehrlichpositive types (types 7 and 8) [120]. From further samples (samples 9 and 10), compounds 160, 161, 163, 168, 199, 200, 212, and 225 and bakkenolide A (629) were
isolated. From another type 2 sample (sample 16), compound 217 was isolated instead
of 216, suggesting the occurrence of diversity within the same chemotype. In addition
to these compounds, eremophilanolides 146 and 417 were isolated by Huang et al.
(sample 14) [113]. Related eremophilanes of both the 10H type (344, 345, 351, 498,
and 499) and 10-OH type (389, 392, 393, and 511) were also isolated by Wang et al.
(sample 15) [121]. Tan et al. obtained dehydrofukinone (5), ligudicins C (18), D (19),
A (22), isopetasin (56), 344, 350, 356, as well as bakkenolide A (629) and aromatic
compounds 1031 and 1032 (samples 11–13) [42, 55, 182]. It is not easy to determine
the relative configuration of 7,11-epoxyeremophilan-8-ones. Compound 22 was
determined to be a 7α,11-epoxide by the NOE effect observed between H 3 -13 and
H 3 -14. Its diastereoisomer, 7β,11-epoxide, is also known [302].
3.27 Ligularia duciformis (C. Winkler) Handel-Mazzetti,
Ligularia konkalingensis Handel-Mazzetti, Ligularia
nelumbifolia (Bureau & Franchet) Handel-Mazzetti,
and Ligularia limprichtii (Diels) Handel-Mazzetti
Ligularia duciformis, L. konkalingensis (Plate 20), and L. nelumbifolia are close to
one another morphologically and are very abundant in the Hengduan Mountains
area of China. Their differentiation is based on the pili on their involucres and on the
length of the pappi [2]. However, from our observations, their morphological characters appear to be very similar. In addition, the three species are indistinguishable
with respect to the two major indices developed by our team, namely, in their root
chemical composition and their evolutionally neutral DNA (Sect. 4). L. limprichtii
is also close to these species. We analyzed 17 L. duciformis (Table 32), nine L. konkalingensis (Table 33), and ten L. nelumbifolia samples as well as one sample of
L. limprichtii (Table 34). The samples were grouped into four chemotypes on the
basis of their root chemical composition: type 1, eremophilane sesquiterpenoids;
type 2, oplopane sesquiterpenoids; type 3, phenylpropanoids; and type 4, having
none of the compounds specified in types 1–3. From a type 1 sample collected in
Yunnan Province (L. duciformis sample 8), fukinone (4) and its derivative 5 were
isolated [36]. Furanoeremophilanes 161 and 228, including cacalol (316) and its
derivative 323, were also obtained together with 15 and 20 from samples collected
in Sichuan Province (L. duciformis samples 19 and 23; L. nelumbifolia samples 6
and 14) [36, 51, 126]. Oplopanes 729, 730, 731, and 732 were isolated from type 2
samples (L. duciformis samples 7, 17, and 21; L. konkalingensis sample 1) [36, 126,
M. Tori and C. Kuroda
analysis [29]. Among them, the chemical compositions of types 1–5 were somewhat
consistent. From samples of these types (samples 1–3 and 5–7), furanoeremophilanes
160, 161, 168, 189, 192, 212, 216, 232, and 247 were isolated, as well as the nonfurano compound 5. From a type 6 sample (sample 8), furanoeremophil-1(10)-ene
derivatives (256, 288, and 291) were obtained. Later, we found two more Ehrlichpositive types (types 7 and 8) [120]. From further samples (samples 9 and 10), compounds 160, 161, 163, 168, 199, 200, 212, and 225 and bakkenolide A (629) were
isolated. From another type 2 sample (sample 16), compound 217 was isolated instead
of 216, suggesting the occurrence of diversity within the same chemotype. In addition
to these compounds, eremophilanolides 146 and 417 were isolated by Huang et al.
(sample 14) [113]. Related eremophilanes of both the 10H type (344, 345, 351, 498,
and 499) and 10-OH type (389, 392, 393, and 511) were also isolated by Wang et al.
(sample 15) [121]. Tan et al. obtained dehydrofukinone (5), ligudicins C (18), D (19),
A (22), isopetasin (56), 344, 350, 356, as well as bakkenolide A (629) and aromatic
compounds 1031 and 1032 (samples 11–13) [42, 55, 182]. It is not easy to determine
the relative configuration of 7,11-epoxyeremophilan-8-ones. Compound 22 was
determined to be a 7α,11-epoxide by the NOE effect observed between H 3 -13 and
H 3 -14. Its diastereoisomer, 7β,11-epoxide, is also known [302].
3.27 Ligularia duciformis (C. Winkler) Handel-Mazzetti,
Ligularia konkalingensis Handel-Mazzetti, Ligularia
nelumbifolia (Bureau & Franchet) Handel-Mazzetti,
and Ligularia limprichtii (Diels) Handel-Mazzetti
Ligularia duciformis, L. konkalingensis (Plate 20), and L. nelumbifolia are close to
one another morphologically and are very abundant in the Hengduan Mountains
area of China. Their differentiation is based on the pili on their involucres and on the
length of the pappi [2]. However, from our observations, their morphological characters appear to be very similar. In addition, the three species are indistinguishable
with respect to the two major indices developed by our team, namely, in their root
chemical composition and their evolutionally neutral DNA (Sect. 4). L. limprichtii
is also close to these species. We analyzed 17 L. duciformis (Table 32), nine L. konkalingensis (Table 33), and ten L. nelumbifolia samples as well as one sample of
L. limprichtii (Table 34). The samples were grouped into four chemotypes on the
basis of their root chemical composition: type 1, eremophilane sesquiterpenoids;
type 2, oplopane sesquiterpenoids; type 3, phenylpropanoids; and type 4, having
none of the compounds specified in types 1–3. From a type 1 sample collected in
Yunnan Province (L. duciformis sample 8), fukinone (4) and its derivative 5 were
isolated [36]. Furanoeremophilanes 161 and 228, including cacalol (316) and its
derivative 323, were also obtained together with 15 and 20 from samples collected
in Sichuan Province (L. duciformis samples 19 and 23; L. nelumbifolia samples 6
and 14) [36, 51, 126]. Oplopanes 729, 730, 731, and 732 were isolated from type 2
samples (L. duciformis samples 7, 17, and 21; L. konkalingensis sample 1) [36, 126,
M. Tori and C. Kuroda