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A new pentacyclic triterpene 3-O-β-(E)-(4-O-acetylferuloyl)-lupeol (1) possessing an unusual (E)-acetylferuloyl moiety at C-3 and a new bicoumarin 7,7′-dimethoxy-6,6′-dicoumarinyl ether (2) were isolated from the liana Landolphia lucida K. Schum, along with fourteen previously known compounds 3-16, where methandriol dipropionate (3) and 2,3-bis-(4-hydroxy-3-methoxy-benzyl)-dimethyl- succinate (5) were obtained for the first time from natural sources. The structures of the new compounds were established on the basis of extensive 1D and 2D NMR spectroscopy, and HRMS data analyses. The absolute configuration of 1 was determined by circular dichroism (CD) spectroscopy. Furthermore, compounds 1 and 2 had exhibited a significant antibacterial activity against Escherichia coli (ATCC 25922) with MIC values of 2.3 μM and 4.6 μM, respectively; while compounds 4 and 5 showed antiglycation and α-glucosidase inhibitory activities.

Kadsura heteroclita Roxb. Craib. (Schisandraceae), is a vine plant mainly distributed in southwest part of China. A new dibenzocyclooctadiene lignan, kadsulignan W (1), along with eleven known lignans (2-12) were isolated from chloroform soluble fraction of stems of Kadsura heteroclita. The structure of new lignan was elucidated by extensive spectroscopic techniques, namely one- and two-dimensional NMR spectroscopy, and HRESI-MS analysis. The absolute configuration of the biphenyl ring in the new dibenzocyclooctadiene lignan was discerned by circular dichroism (CD) spectroscopy. Antioxidative effects of these compounds were evaluated on human isolated neutrophils, and compounds 5, 8, 9, and 10 were found to be strongly active with the IC50 of 36.68, 34.41, 35.97, and 33.65 µM, respectively. Furthermore, compound 8 was also found to be cytotoxic against human gastric cancer cells (BGC 823), and human cervical cancer cell lines (HeLa) with the IC50 values of 11.0, and 23.8 µM, respectively.

One new methoxylated flavonoid derivative, plectranmicin (1) and one new monoterpene derivative, plectranmicinol (2), together with seven known compounds including 5-hydroxy-3,7,2′,4′-tetramethoxyflavone (3); 5,7-dihydroxy-3,2′,4′-trimethoxyflavone (4); 7-hydroxy-5,6,4′-trimethoxyflavone (5); 3-epi-betulinic acid (6); 3-O-β-D-glucopyranosyl stigmasterol (7); β-sitosterol (8) and 4-epi-fridelin (9) were isolated from the whole plant of Plectranthus glandulosus Hook. The structures of these compounds were established on the basis of extensive analysis of their spectroscopic data, as well as one and two-dimensional NMR experiments. The absolute configuration of compound 2 was established by X-ray crystallographic analysis. Although compounds 3 and 4 have been previously reported as synthetic compounds, it is the first time that these compounds are isolated from a natural source. Compounds 1–5 were evaluated for their antioxidant activity using the scavenging activity of the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH°) and the Ferric Reduction Antioxidant Power (FRAP). The results obtained showed that compounds 1 and 2 displayed significant antioxidant activity with IC50 values of 0.208 and 0.322 μM/mL; 0.185 and 0.339 μM/mL respectively whereas, the activity of the other was moderated. It is the first time that the antioxidant activity of these compounds are reported.

Phytochemical studies on the root of Abrus precatorius Linn. (Fabaceae), leads towards the identification of four undescribed (abruquinones M, N, O, and P), and seven known abruquinones, (abruquinones A, E, B, F, I, D, and G). Spectroscopic analyses (1D, and 2D NMR, HRESI-MS) were used in elucidating structures of the all compounds. Evaluation of anticancer activities of the isolated isoflavanquinones revealed that abruquinones M, and N showed cytotoxicity against oral CAL-27 (IC50 values 6.48 and 5.26 μM, respectively), and colon (Caco-2) cell lines (IC50 values 15.79 and 10.33 μM, respectively). Abruquinone M also inhibited the growth of lung cancer cells (NCI–H460) with IC50 of 31.33 μM. The isolated isoflavanquiones also showed potent anti-inflammatory potential through phagocyte oxidative burst and pro-inflammatory cytokine TNF-α inhibition in vitro. These findings suggest isoflavanquinones from A. precatorius roots as candidates for further research in cancer treatment.

In the present work, we reported the triterpenoids isolated from n-butanol fraction of Kadsura heteroclita which is a Tujia ethnomedicine with trivial name “Xuetong”. This effort resulted in the isolation of six unpresented triterpenoids xuetongsu A-F (1–6), along with five known triterpenoids (7–11). The structures of the reported compounds were established on the 1D, and 2D NMR and HRESIMS spectra, along with CD spectroscopic analysis. Moreover, the absolute stereochemistry of compound 7 was determined by X-ray diffraction analysis. Antioxidant and cytotoxic activities were evaluated for all isolated compounds, compound 7 shown weak cytotoxic activity against HL-60 with IC50 value of 50.0 μM.

In the present work, we take advantage of the characteristic NMR signal (δC-10 = 96.0–99.9) for guiding the isolation of schinortriterpenoids (SNTs) from n-butanol fraction of stems of Kadsura heteroclita which is a Tujia ethnomedicine with trivial name “Xuetong”. This effort resulted in the identification of three unreported 3,4:9,10-disecocycloartane triterpenoids xuetongdilactones A-C and three undescribed SNTs xuetongdilactones D-F, along with two known SNTs, namely, wuweizidilactone B and micrandilactone B. The structures of the unreported compounds were established based on 1D, and 2D NMR, HRESIMS, and ECD spectroscopic data analysis. The absolute stereochemistry of xuetongdilactone A was determined by X-ray diffraction analysis along with ECD calculation. The antioxidant and cytotoxic activities were evaluated for all the isolated compounds.

As part of our continual efforts to exploit &lsquo, Tujia Ethnomedicine&rsquo, for their pharmacophoric functionalities, we herein investigated Kadsura heteroclita collected from a deep Wulin mountain area in northern Hunan province. The current study resulted in the isolation of three new sesquiterpenes: 6&alpha, 9&alpha, 15-trihydroxycadinan-4-en-3-one (1), (+)-3,11,12-trihydroxycalamenene (2), (&ndash, )-3,10,11,12-tetrahydroxy-calamenene (3), along with four known sesquiterpenes (4&ndash, 7), and a cytochalasin H (8). Their chemical structures were elucidated by 1D-, and 2D-NMR spectroscopy, and HRESI-MS, CD spectrometry. The antioxidant, and cytotoxic activities of the compounds were evaluated. Compound 8 exhibited a strong antioxidant effect with an IC50 value of 3.67 &micro, M on isolated human polymorphonuclear cells or neutrophils.