New Sesquiterpenoids from Ligularia duciformis

Abstract

From the whole plants of Ligularia duciformis, four new sesquiterpenoids, 3b-acetoxy-6b-methoxyeremophila-7(11),9(10)-dien-12,8b-olide (1), 3b-acetoxy-8a-hydroxy-6b-methoxyeremophila-7(11),9(10)-dien-12,8b-olide (2), 3b-acetoxy-10b-hydroxy-6b,8b-dimethoxyeremophil-7(11)-en-12,8a-olide (3), and 3b-acetoxy-6b,8b,10b-trihydroxyeremophil-7(11)-en-12,8a-olide (4) were isolated. Their structures were established by high-field NMR techniques ( 1 H, 1 H-COSY, 13 C-APT, HMQC, HMBC, and NOESY) and HR-ESI-MS analysis, together with comparison of the spectroscopic data with those of structurally related compounds. In addition, the cytotoxicity of the new compounds against human hepatic cancer cells Bel-7402, human pneumonic cancer cells A-549, and human colonic cancer cells HCT-8 were evaluated, the new compounds showed no cytotoxicity against the three tumor cells (all IC 50 values > 200 mm).Introduction. -Ligularia duciformis (Compositae) is a perennial grass, which is native in the southwest area of mainland China. Its roots are used as a Chinese folk medicine for the treatment of inflammation and apoplexy [1], showing effect on nourishing lung and relieving a cough. Sesquiterpenoids, especially eremophil-7(11)-en-12,8-olides have been isolated from other plants in Ligularia as the characteristic components of the genus [2 -4]. However, phenolic compounds were previously reported from the dried root of L. duciformis collected in Hubei Province [5]. Herein, we studied the constituents of the MeOH extract of the whole plant of L. duciformis, collected in the southwest area of Sichuan Province, where the average height is more than 3000 meters. As a result, four new eremophil-7(11)-en-12,8-olides 1 -4 were isolated. In this work, we describe the isolation and structural elucidation of these compounds. Furthermore, all new compounds were evaluated for their cytotoxicity against human hepatic cancer cells Bel-7402, human pneumonic cancer cells A-549, and human colonic cancer cells HCT-8.

Chemical and Genetic Study of Ligularia duciformis and Related Species in Sichuan and Yunnan Provinces of China

“…Samples 1, 3, and 4 grew in the southernmost collection areas and Samples 2 and 5 in the easternmost harvesting areas (Fig. In addition, the L. duciformis sample reported to produce eremophilane-type sesquiterpene lactones by Wang et al [23] was also collected on the edge of the distribution area in Meigu, ca. These were located on the edge of the distribution area of these plants [1].…”

3β-Acetoxy-8β,10β-dihydroxy-6β-methoxyeremophil-7(11)-en-8,12-olide

“…The project was supported by the 985 Project (MUC985) Minzu University of China, and the Major Project for Young Teachers in Minzu University of China CUN10A, together with the 'Programme of Introducing Talents of Discipline to Universities' (B08044), and the 'Project for Scientific and Technical Achievements in Industrialization', Beijing Education Commission. spectra data and compared with the previous reports (Zhang et al, 1998;Wang et al, 2008). Herewith we present its crystal structure.…”

“…H-atom parameters constrained w = 1/[σ 2 (F o 2 ) + (0.0856P) 2 ] where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.29 e Å −3 Δρ min = −0.36 e Å −3 Extinction correction: SHELXL97 (Sheldrick, 2008), Fc * =kFc[1+0.001xFc 2 λ 3 /sin(2θ)] -1/4 Extinction coefficient: 0.130 8Special details Experimental. Since the two skeleton methyl group in eremophilenolides are biogenic b position, we draw the relative stereochemistry of the title eremophilenolide, by reference to the structures of related eremophilenolides in Wang at al. (2008) and Zhang, et al (1998) although the absolute configuration could not be reliably determined from anomalous dispersion effects.…”