Sesquiterpenes from Ligularia intermedia

Eremophilane sesquiterpene lactones from Ligularia intermedia Nakai of Shanxi

“…13 C NMR (DEPT, 100 MHz, CDCl 3 , δ, ppm): 8.24 (q, C-13), 18.74 (t, C-2), 20.30 (q, C-14), 20.48 (t, C-1), 23.14 (t, C-3), 25.24 (t, C-9), 36.95 (d, C-10), 41.27 (d, C-4), 41.42 (s, C-5), 81.63 (d, C-6), 114.68 (s, C-11), 120.08 (s, C-7), 138.56 (s, C-12), 150.78 (s, C-8), 176.65 (s, C-15). All the above data were consistent with the furanoeremophilan-4β,6α-olide reported in the literature [7,9].…”

“…The most widespread constituents of this genus are pyrrolizidine alkaloids and sesquiterpenes [2,3]. Some research groups have carried out phytochemical studies on this plant [4][5][6][7][8]. However, it is well known that the climate and ecological environment can affect the chemical constituents of plants.…”

New Eremophilanolides from Ligularia hodgsonii

“…2), C(10) was inferred to be oxygenated. By comparison of the NMR data of 4 with those of the known sesquiterpene 10b-hydroxyeremophil-7(11),8(9)-dien-6a,15b;8a,12-diolide [7], it was found that the 1 H and 13 C spectral data of both compounds were nearly the same, except that the C-atom shifts of the signals for C(1), C(9), and C(10) indicated that 4 is epimeric at C(10). In addition, 10b-hydroxyeremophil-7(11),8(9)-ene6a,15b;8a,12-diolide was obtained by letting 4 stand in DMSO for prolonged periods þ ).…”

New Eremophilane-Type Sesquiterpenes fromLigularia lapathifolia

“…Original Paper d H = 7.07, (H-12, 1H, s)] and an angeloyloxy moiety displayed, suggesting 7 to be a furanosesquiterpene. By comparison of its NMR data with those of a known sesquiterpene, furanoeremophilan-14b,6a-olide [6], compound 7 was identified as 3b-angeloyloxyeremophila-7,11-dien-14b,6a-olide due to the presence of an oxygenated methine carbon signal at d C-3 = 65.2 in 7 instead of the methylene carbon signal at d C-3 = 23.3 in 10.…”

“…32), 159(10), 149 (12), 135 (17), 128 (11), 115 (17), 100 (52), 91 (27), 83 (88), 67 (32).3b-Angeloyloxy-8,12-expoy-12a-hydroxy-8b-methoxyeremophil-7(11)-en-14b,6a-olide(6): Amorphous powder, m. p. 214 ± 215 8C; [a] D 25 : + 56.58 (c 0.67, CHCl 3 ); IR (KBr): n max = 3500, 2940, 1772, 1685, 1457, 1256, 1204, 1094, 1012, 936 cm ±1 ; 1 H-NMR and 13 C-NMR spectral data, see Tables 1 and 2; HR-EIMS: found: 392.4423 [M + ] (calcd. for C 21 H 28 O 7 : 344.4001); EIMS: m/z…”