Sesquiterpene coumarins from Ferula gumosa

A new sesquiterpene coumarin, gumosin (1), two new sesquiterpene coumarin glycosides, gumosides A (2) and B (3), and 10 known compounds, namely, cauferoside (4), feselol (5), conferoside, ferilin, ferocaulidin, ligupersin A, conferol, and daucosterol, and the phenolic compounds acantrifoside E and 4-hydroxybenzoic acid 4-(6-O-sulfo)glucopyranoside, were isolated from a methanolic extract of Ferula gumosa roots. The structures of 1-3 were elucidated by spectroscopic data interpretation. The cytotoxic activity of the sesquiterpene coumarin derivatives was evaluated against a small panel of cancer cell lines.     

Sesquiterpene coumarins from Ferula fukanensis and nitric oxide production inhibitory effects

Six new sesquiterpene coumarin derivatives, 2,3-dihydro-7-hydroxy-2R,3R-dimethyl-2-[4,8-dimethyl-3(E),7-nonadien-6-onyl]furo[3,2-c]coumarin (4), fukanefuromarin A (5), fukanefuromarin B (6), fukanefuromarin C (7), fukanefuromarin D (8), and fukanemarin A (9), were isolated from a 80% aqueous methanol extract of the roots of Ferula fukanensis. The structures were elucidated on the basis of spectral evidence, especially heteronuclear multiple-bond connectivity (HMBC), nuclear Overhauser exchange spectroscopy (NOESY), and high-resolution MS. An extract of F. fukanensis (FFE) and the sesquiterpene coumarin derivatives inhibited nitric oxide (NO) production and inducible NO synthase (iNOS) gene expression by a murine macrophage-like cell line (RAW 264.7), which was activated by lipopolysaccharide (LPS) and recombinant mouse interferon-gamma (IFN-gamma).     

Sesquiterpene coumarins and related derivatives from Ferula pallida

Six new compounds-two sesquiterpene coumarins, pallidones A and B (1, 2), and four related derivatives, pallidones C-F (3-6), as well as two known sesquiterpene coumarins, feselol (7) and conferol (8), have been isolated from the EtOAc extracts of the roots of Ferula pallida. All structures of these compounds were determined on the basis of spectral evidence, especially 2D NMR ((1)H-(1)H COSY, HSQC, HMBC, and NOESY) and HRMS. The possible biosynthetic pathway of pallidones C-F (3-6) is discussed.     

Mitchellenes A-E, cyclic sesquiterpenes from the Australian plant Eremophila mitchellii

Chemical investigations of the Australian plant Eremophila mitchellii resulted in the isolation of the novel tetracyclic sesquiterpene lactones mitchellenes A-C (1-3), the new sesquiterpene acids mitchellenes D and E (4 and 5), and the previously reported natural products 14-hydroxy-6,12-muuroloadien-15-oic acid (6), casticin, and centaureidin. The chemical structures of all compounds were determined by extensive 1D/2D NMR and MS data analysis. Mitchellenes A-C are the first tetracyclic sesquiterpene lactones to be reported; a biosynthetic pathway is proposed for these unique secondary metabolites.     

Antidiabetic dimeric guianolides and a lignan glycoside from Lactuca indica

Three novel sesquiterpene lactones, lactucain A (1), B (2), and C (3), and a new furofuran lignan, lactucaside (4), were isolated from Lactuca indica along with nine known compounds, 11beta,13-dihydrolactucin, cichoriosides B, quercetin, quercetin 3-O-glucoside, rutin, apigenin, luteolin, luteolin 7-O-glucuronide, and chlorogenic acid. Among these compounds, latucain C (3) and lactucaside (4) showed significant antidiabetic activity.     

Perspicamides A and B, quinolinecarboxylic acid derivatives from the Australian ascidian Botrylloides perspicuum

Two novel quinoline-2-carboxylic acid derivatives, perspicamides A (2) and B (3), were isolated from the Australian ascidian Botrylloides perspicuum. Extraction of the freeze-dried ascidian with methanol and purification of the extract by C18 MPLC followed by repeated C18 HPLC yielded the new compounds 2 and 3 as well as the known compounds botryllamides A-C (4-6). The structures of 2 and 3 were determined from analysis of 2D NMR spectra.     

Izumiphenazines A-C: isolation and structure elucidation of phenazine derivatives from Streptomyces sp. IFM 11204

Three new phenazine derivatives, named izumiphenazines A-C (1-3), and the known phenazine-1,6-dicarboxylic acid (4) were isolated from Streptomyces sp. IFM 11204. The structures of the isolated compounds were elucidated by means of spectroscopic methods including UV, IR, HRESIMS, and 1D and 2D NMR. Compounds 1-3 were evaluated for their activity in overcoming TRAIL (TNF-related apoptosis-inducing ligand) resistance in human gastric adenocarcinoma cells. Compounds 2 (30 μM) and 3 (20 μM) in combination with TRAIL showed synergistic activity in sensitizing TRAIL-resistant AGS cells.     

New glycosphingolipids from the fungus Catathelasma ventricosa

Three new glycosphingolipids with a cis-Delta(17)-fatty acyl moiety, namely, catacerebrosides A-C (1-3), along with two known glycosphingolipids, cerebrosides B and D, six known ergostane-type sterols, and tyrosamine were isolated from the fungus Catathelasma ventricosa. The structures of 1-3 were elucidated on the basis of spectroscopic analysis and chemical methods.     

Coumarins from the fruits of Cnidium monnieri

Two novel biscoumarins, cnidimonal (1) and cnidimarin (2), and two new coumarin derivatives, 5-formylxanthotoxol (3) and 2'-deoxymeranzin hydrate (4), were isolated from a traditional Chinese crude drug, the fruits of Cnidium monnieri, together with 15 known compounds. Among the known compounds, five of the minor compounds were isolated for the first time from this plant. The structures of 1-4 were determined with the use of spectroscopic methods.     

Sesquiterpene lactones from Inula britannica and their cytotoxic and apoptotic effects on human cancer cell lines

Three new sesquiterpenes (1-3), together with four known sesquiterpene lactones, were isolated from the flowers of Inula britannica var. chinensis. Structures were established on the basis of high-field 1D and 2D NMR methods supported by HRMS. All sesquiterpene lactones were tested for cytotoxicity as well as apoptotic ratio in human COLO 205, HT 29, HL-60, and AGS cancer cells. Compounds 3 and 4, two alpha-methylene gamma-lactone-bearing sesquiterpenes, were modestly active in these assays.     

Alkaloids with human delta-opioid receptor binding affinity from the Australian rainforest tree Peripentadenia mearsii

Three new pyrrolidine alkaloids, peripentonine A-C ( 2- 4), one known pyrrolidine alkaloid, peripentadenine ( 1), and one novel indolizidine alkaloid, mearsamine ( 5), were isolated from the leaves of Peripentadenia mearsii and their structures determined by 1D and 2D NMR spectroscopy. Peripentonines A ( 2) and B ( 3) were isolated as a 1:1 mixture of inseparable diastereomers. Mearsamine ( 5) contains a novel tricyclic ring system. Peripentadenine and peripentonines A/B and C showed receptor binding affinity for the human delta-opioid receptor with IC 50 values of 11.4, 69.2, and 30.9 microM, respectively. Mearsamine did not bind to the delta-opioid receptor.     

Tripfordines A-C, sesquiterpene pyridine alkaloids from Tripterygium wilfordii, and structure anti-HIV activity relationships of Tripterygium alkaloids

Three new sesquiterpene pyridine alkaloids, tripfordines A-C (1-3), were isolated from an ethanolic extract of the roots of Tripterygium wilfordii, along with eight known pyridine alkaloids, and tested for in vitro cytotoxic and anti-HIV activity. The structures of the new compounds were established on the basis of spectroscopic data interpretation. Anti-HIV structure-activity relationships (SAR) for this compound type are proposed on the basis of the screening results from the newly isolated compounds and prior data of known sesquiterpene pyridine alkaloids. The position of a carboxyalkyl chain on the pyridine moiety was not critical since both 2'- and 4'-substituted compounds exhibited high anti-HIV activity (EC(50) 0.1 microg/mL). In contrast, a hydroxy group at C-8' (carboxypropyl side chain) or C-9' (carboxybutyl side chain) was found to affect anti-HIV activity.     

Furan metabolites from the sponge-derived yeast Pichia membranifaciens

Five new compounds, pichiafurans A-C (1-3) and pichiacins A and B (4 and 5), along with five known compounds (6-10), have been isolated from the yeast Pichia membranifaciens derived from a marine sponge Petrosia sp. Their structures were elucidated by 1D and 2D NMR and mass spectrometry techniques. Pichiafurans are rare examples of monofurano metabolites isolated from yeast.     

Structure and absolute configuration of clerodane diterpene glycosides and a rearranged cadinane sesquiterpene glycoside from the stems of Tinospora sinensis

Three new clerodane diterpene glycosides, tinosposinensides A-C ( 1- 3), and a new rearranged cadinane sesquiterpene glycoside, tinosinenside ( 4), were isolated from the stems of Tinospora sinensis. The structure including the relative configuration was elucidated on the basis of spectroscopic analysis. The absolute configuration was determined by application of the modified Mosher's method and chemical transformation. The inhibitory activities of the isolated compounds against alpha-glucosidase are also described.     

Tasnemoxides A-C, new cytotoxic cyclic norsesterterpene peroxides from the Red Sea sponge Diacarnus erythraenus

Tasnemoxides A-C (1-3), three new cytotoxic cyclic norsestertepene peroxides, were isolated from the Red Sea sponge Diacarnus erythraenus, together with the known compound sigmosceptrellin B (4). The structural determination of the isolated compounds was based on extensive 1D and 2D NMR studies and mass spectral determinations. Compounds 1-3 showed moderate cytotoxicity against three cancer cell lines.     

Globosumones A-C, cytotoxic orsellinic acid esters from the Sonoran desert endophytic fungus Chaetomium globosum

Three new esters of orsellinic acid, globosumones A-C (1-3), and three known compounds, orsellinic acid (4), orcinol, and trichodion (5), were isolated from Chaetomium globosum endophytic on Ephedrafasciculata (Mormon tea). The structures of the new compounds 1-3 were established spectroscopically, which included 2D NMR experiments and 1H NMR studies on Mosher's ester derivatives. All compounds were evaluated for inhibition of cell proliferation in a panel of four cancer cell lines, NCI-H460 (non-small cell lung cancer), MCF-7 (breast cancer), SF-268 (CNS glioma), and MIA Pa Ca-2 (pancreatic carcinoma), and normal human fibroblast cells (WI-38). Only globosumones A (1) and B (2) were found to be moderately active.     

Epoxydons and a pyrone from the marine-derived fungus Nigrospora sp. PSU-F5

Nigrospoxydons A-C (1- 3) and nigrosporapyrone (4), four new metabolites, were isolated from the marine-derived fungus Nigrospora sp. PSU-F5 together with nine known compounds. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. The antibacterial activity against the standard Staphylococcus aureus ATCC 25923 and methicillin-resistant S. aureus was evaluated.     

Phenolic constituents of Gnetum klossii

Four new phenolic derivatives, gnetofurans A-C (1-3) and dihydropinosylvindiol (4), were isolated from a methanol-soluble extract of the stems of Gnetum klossii, together with nine known compounds [gnetifolin F (5), isorhapontigenin, gnetulin, gnetins E and C, latifolol, gnetol, (-)-epsilon-viniferin, and trans-resveratrol]. The structures of the new compounds were determined by spectral data analysis.     

Terpenoids from Chloranthus serratus and their anti-inflammatory activities

Seven new terpenoids, including two sesquiterpene dimers (1, 2), two norditerpenoids (3, 4), and three sesquiterpenes (5-7), along with six known sesquiterpene dimers and four known sesquiterpenes were isolated from the whole plant of Chloranthus serratus. Their structures and relative configurations were elucidated on the basis of spectroscopic data analysis. The absolute configuration of 1 was determined by the CD exciton chirality method. These isolates were evaluated for their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells. Compound 2 and two known compounds, shizukaols B and D, showed significant anti-inflammatory activities, with IC(50) values of 0.22, 0.15, and 7.22 μM, respectively.     

Zinagrandinolides A-C, cytotoxic delta-elemanolide-type sesquiterpene lactones from Zinnia grandiflora

Three new delta-elemanolide-type sesquiterpene lactones, zinagrandinolides A-C (1-3), and the known delta-elemanolide 4 have been isolated by a bioassay-guided fractionation of a cytotoxic hexane extract of the aerial parts of Zinnia grandiflora. The structures of 1-3 were determined on the basis of high-resolution mass and NMR data. All compounds exhibited strong cytotoxicity against the cancer cell lines NCI-H460, MCF-7, SF-268, and MIA Pa Ca-2 and the normal human fibroblast cell type WI-38, but none showed significant selectivity.