Bioactive eudesmane and germacrane derivatives from Inula wissmanniana Hand.-Mazz.

Phytochemical investigation of Inula wissmanniana Hand.-Mazz. afforded 21 eudesmane and germacrane derivatives, including rare 4,5-secoeudesman-12,5-olide, eudesman-12,5-olide, 3,4-secoeudesman-12-oic acid, and germacra-4-en-12,6-olides. Their structures were elucidated by combinative analyses of MS, NMR, electronic circular dichroism, and X-ray crystallography data. Moreover, most of the isolates exhibited inhibition against lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophages and cytotoxicity in HepG2, PC-3, and MGC-803 tumor cells.

Cheng XR ，Zhang SD ，Wang CH ，Ren J ，Qin JJ ，Tang X ，Shen YH ，Yan SK ，Jin HZ ，Zhang WD ... -  《-》

New sesquiterpenic acids from Inula wissmanniana.

Eight new (1-8) and two known (9 and 10) sesquiterpenic acids featuring α-methylene-γ-carboxyl units were isolated from the whole plants of Inula wissmanniana, along with two new germacranolides (11 and 12). Their structures were elucidated based on detailed spectroscopic analysis, including HRESIMS, 1D and 2D NMR, and X-ray crystallography. Notably, the skeleton of 1 was firstly discovered from nature, while that of 2 was discovered for the second time. All the compounds were evaluated for their inhibition against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages. Compound 11 exhibited the strongest activity with the IC50 value of 1.04 μM.

Cheng XR ，Wang CH ，Wei PL ，Zhang XF ，Zeng Q ，Yan SK ，Jin HZ ，Zhang WD ... -  《-》

Bioactive sesquiterpenoids from the flowers of Inula japonica.

Phytochemical investigation of the flowers of Inula japonica led to isolation of nine sesquiterpenoids, inujaponins A-I, as well as eighteen known ones. These sesquiterpenoids belong to six skeletal-types, including eudesmane, 1,10-seco-eudesmane, germacrane, guaiane, 4,5-seco-guaiane, and pseudoguaiane sesquiterpenoids. Their structures were established by extensive spectroscopic analysis. The absolute configurations of inujaponin A, eupatolide, and deacetylovatifolin were determined by Cu-Kα X-ray crystallographic analysis. Most of the isolated compounds exhibited potent cytotoxicity against HL-60, SMMC-7721, A-549, MCF-7, and SW-480 cancer cell lines, with IC50 values ranging from 1.57 to 22.58 μM. Some selected compounds also possessed significant inhibitory activity against LPS-induced NO production in RAW264.7 macrophages with IC50 values ranging from 1.42 to 8.99 μM.

Wu XD ，Ding LF ，Tu WC ，Yang H ，Su J ，Peng LY ，Li Y ，Zhao QS ... -  《-》

Sesquiterpene lactones from Inula hupehensis inhibit nitric oxide production in RAW264.7 macrophages.

Phytochemical investigation of the aerial parts of Inula hupehensis Ling. led to the isolation and identification of 27 sesquiterpene lactones (1-27), including three new eudesmanolides (3-5), three new germacranolides (9-11), one new xanthanolide (16), two new carabrone derivatives (25-26), and 18 known sesquiterpene lactones. The structures were elucidated by extensive spectroscopic methods and comparison to previously reported spectroscopic data. All compounds were evaluated for their inhibitory effects against LPS-induced nitric oxide production in RAW264.7 macrophages, and compound 5 showed the strongest activity with the IC₅₀ value of 3.2 ± 0.4 µM.

Qin JJ ，Zhu JX ，Zeng Q ，Cheng XR ，Zhang SD ，Jin HZ ，Zhang WD ... -  《-》

Eudesmane-type sesquiterpene derivatives from Laggera alata.

Ten eudesmane-type sesquiterpene derivatives (1-10), including six cuauhtemone derivatives (1-6), one di-norsesquiterpene (3-oxo-di-nor-eudesma-4-en-11-oic acid, 7), and three eudesmane glycosides (alatoside F-H, 8-10) were isolated from the whole plants of Laggera alata together with 12 known compounds. Their structures were elucidated on the basis of extensive spectroscopic analysis, acid hydrolysis, and compounds 1 and 7 were studied by single-crystal X-ray diffraction analysis. The absolute configuration of 1 was determined by the application of the modified Mosher's method. All of the isolated eudesmane-type sesquiterpenes were evaluated for their cytotoxic activities on six human cancer cell lines, but all of the compounds were inactive on the tested cell lines in the concentration of 100 μg/mL.

Wang GC ，Li GQ ，Geng HW ，Li T ，Xu JJ ，Ma F ，Wu X ，Ye WC ，Li YL ... -  《-》