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Six previously undescribed C 17 -guaianolides, a previously undescribed guaianolide alkaloid, and two previously undescribed guaianolides as well as 10 known guaianolides were obtained from an ethanol extract of Ainsliaea yunnanensis Franch. The chemical structures of all previously reported sesquiterpenoids were determined by extensive NMR spectroscopic analysis in combination with a modified Mosher's method. All isolates were in vitro screened for inhibitory effect against nitric oxide release in RAW 264.7 macrophages stimulated by LPS. Zaluzanin C remarkably inhibited the production of nitric oxide with an IC 50 value of 6.54 μM., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Nine lanostane-type triterpenoids were isolated from branches and leaves of Abies faxoniana, along with 10 known compounds. Two were isolated as inseparable mixtures of epimers at C-23 of the γ-lactone ring that had a lactol structure. The structures of the nine compounds were established by spectroscopic analysis and circular dichroism (CD) data. The absolute configurations at the stereogenic centres of two of the known compounds were confirmed by X-ray crystallography. One compound showed cytotoxic activities against HCT-116, MCF-7, and A549 cells with IC50 values of 8.9, 7.6, and 4.2μM, respectively. The isolated compounds were tested for their effects on human DNA topoisomerases I and II. One was found to be a selective inhibitor of human topo II activity with an IC50 value of 53.5μM, which was comparable to that of the topo II inhibitor etoposide (IC50=49.6μM)., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

During a survey on chemical constituents of Abies nukiangensis, seven previously unreported compounds, including six triterpenes (1-6) and one phenol (7) were isolated and characterized, together with 37 known miscellaneous chemical constituents. The structures of compounds 1-7 were established mainly by extensive analysis of the 1D and 2D NMR, as well as HRMS data. The absolute configurations of compounds 1 and 8 were confirmed unambiguously by the Cu-Kα X-ray crystallography. Compounds 3 and 8-10 showed significant anti-hepatitis C virus effects with EC50 values of 3.73, 2.67, 1.33 and 2.25μM, respectively., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

γ-Hydroxynitrile glucosides (prinsepicyanosides A-E) were isolated alongside 11 known compounds from seeds of Prinsepia utilis Royle. Their structures were determined by detailed analysis of NMR and MS spectroscopic data. The relative configuration of prinsepicyanoside C was established by Cu-Kα X-ray crystallography. Prinsepicyanoside A, osmaronin, and 4-(hydroxylmethyl)-5H-furan-2-one exhibited borderline antibacterial activity against Salmonella gallinarum, Vibrio parahaemolyticus, and Vibrio cholera with MIC values of 30.1, 20.7, and 22.8μg/mL, respectively., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

HPLC-PDA-MS and TLC analysis were used to look for minor cytotoxic chlorinated valepotriates from whole plants of Valeriana jatamansi (syn. Valeriana wallichii DC.). This resulted in isolation of 15 chlorinated valepotriates, designated as chlorovaltrates A-O, together with six known analogues, (1S,3R,5R,7S,8S,9S)-3,8-epoxy-1,5-dihydroxyvalechlorine, volvaltrate B, chlorovaltrate, rupesin B, (1S,3R,5R,7S,8S,9S)-3,8-epoxy-1-O-ethyl-5-hydroxyvalechlorine, and (1R,3R,5R,7S,8S,9S)-3,8-epoxy-1-O-ethyl-5-hydroxyvalechlorine. Their structures were elucidated by spectroscopic methods including homo- and heteronuclear two-dimensional NMR experiments. Chlorovaltrates K-N, chlorovaltrate and rupesin B showed moderate cytotoxicity against lung adenocarcinoma (A 549), metastatic prostate cancer (PC-3M), colon cancer (HCT-8) and hepatoma (Bel 7402) cell lines with IC₅₀ values of 0.89-9.76 μM., (Copyright © 2012 Elsevier Ltd. All rights reserved.)