New Guaiane-Type Sesquiterpene and Norsesquiterpene from Alisma plantago-aquatica and Their Xanthine Oxidase Inhibitory Activity.

A new sesquiterpene (1) and a new norsesquiterpene (2) belonging guaiane-type skeleton together with six known compounds (3-8) were isolated from the rhizomes of Alisma plantago-aquatica. Their structures were determined by HR-ESI-MS, 1D and 2D NMR spectroscopic methods. Absolute configurations of new compounds were established by experimental and TD-DFT computational ECD spectra. Compounds 1-8 exhibited xanthine oxidase inhibitory activity with their IC50 values in range of 9.4-66.7 µM. The sesquiterpenoids 1-5 displayed the inhibitory activity and hence they could be potential xanthine oxidase inhibitors from A. plantago-aquatica.

Myobontioids A-D and antifungal metabolites from the leaves of Myoporum bontioides A. Gray.

A new sesquiterpene glucoside (1), two new norsesquiterpenes (2, 3), and a new homomonoterpene (4), named myobontioids A-D respectively, along with twelve known flavonoids and lignans (5-16) were isolated from Myoporum bontioides A. Gray. Flavanones 5-11 specifically inhibited Phytophthora capsici and Magnaoeporthe grisea at the concentrations of 125, 250 and 500 µg.mL-1. Notably, the new compound 4 possessed a strong activity against Phytophthora capsici with IC50 below 63.5 µg.mL-1 and 90.4% inhibition at 125 µg.mL-1.

[A new nor-sesquiterpene glycoside from Corydalis edulis].

This study is to investigate the chemical constituents from the whole plant Corydalis edulis. The chemical constituents were separated and purified by macroporous resin D101, silica gel, Sephadex LH-20, ODS, and semi-preparative HPLC. Their structures were determined by physicochemical properties and spectroscopic data. Four compounds were isolated from the dichloromethane and water extracts of the whole plant C. edulis, and identified as 6'-ß-D-xylosylicariside B2(1),(3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one(2), loliolide(3), and 5,5'-dimethoxybiphenyl-2,2'-diol(4), respectively. Compound 1 is a new compound, of which the absolute configuration was established by electronic circular dichroism(ECD) calculations. Compound 4 is obtained from the plants of Papaveraceae family for the first time. Compounds 2 and 3 are firstly isolated from the Corydalis genus.

Acyclic diterpene and norsesquiterpene from the seed of Aphanamixis polystachya.

Aphanamoxene A-D (1-4), three new acyclic diterpene derivatives and one new acyclic norsesquiterpene were isolated from the seed of Aphanamixis polystachya. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D and 2D NMR and HRESIMS. And the absolute configuration of 1 was achieved by Mosher method. These acyclic terpenoids (1-4) showed obvious nitric oxide production inhibitory activity on lipopolysaccharide-Induced RAW264.7 macrophages with IC50 values of 17.6 ± 1.4, 9.8 ± 0.7, 16.6 ± 1.2, and 14.2 ± 0.9 µM, respectively.

Chemical constituents from the bark of bauhinia purpurea and their NO inhibitory activities.

Phytochemical studies led to the isolation of a new phenylpropanoid glucoside, named purpuroside (1), along with eight known compounds (2-9) from the bark of Bauhinia purpurea. The structure of the new compound was elucidated on the basis of its spectroscopic data. The absolute configuration of compound 2 was verified by X-ray diffraction analysis. Compounds 1, 2, 7, 8, and 9 inhibited NO production in mouse peritoneal macrophages with IC50 values from 35.5 to 63.0 µM.

Arahyside A, a new norsesquiterpene from Arachis hypogaea.

Six compounds were isolated from the stems and leaves of Arachis hypogaea, including a new norsesquiterpene, arahyside A (1), and five known compounds, 4-(2-methoxyethyl)benzene-1,2-diol (2), (1(R,S),2(R,S))-1-phenylpropane-1,2-diol (3), tachioside (4), 1,3-benzenediol (5), demethylmedicarpin (6). Extensive spectroscopic methods, containing HR-EI-MS, NMR and ECD were used for structural elucidation of this new compound 1. Furthermore, its cytotoxicity was evaluated by MTT assay.

A new norsesquiterpene glycoside from fruits of Actinidia arguta / 中草药

Objective: To study the chemical constituents in the fruits of Actinidia arguta. Methods: The compounds were isolated by column chromatography on silica gel, ODS, and Sephadex LH-20, preparative TLC, and semi-preparative HPLC. The structures were established by the analyses of the spectroscopic data. Results: Fifteen compounds were obtained from the n-BuOH fraction of the 75% ethanol extract of the fruits of A. arguta and identified as (2R,6R,9R)-trihydroxy-megastigmane-4,7E-dien-3-one-9-O-β-D- glucopyranoside (1), (6S,9R)-roseoside (2), quercetin-3-O-b-D-galactopyranside (3), astragalin (4), vanillic acid-4-O-β-D- glucopyranoside (5), 1-O-feruloyl-β-D-glucopyranoside (6), ferulic acid-4-O-β-D-glucopyranoside (7), rhodioloside (8), 3-hydroxy-1-(4-O-β-D-glucopyranosyl-3- methoxyphenyl) propan-1-one (9), 5-O-caffeoyl quinic acid methyl ester (10), 5-O-caffeoyl quinic acid butyl ester (11), 5-O-feruloyl quinic acid methyl ester (12), 5-O-coumaroyl quinic acid methyl ester (13), caffeic acid (14), and protocatechuic acid (15). Conclusion: Compound 1 is a new norsesquiterpene glycoside with the megastigmane scaffold, named actinargutaside A. Compounds 2, 5, and 7-13 are isolated from the Actinidia genus for the first time and compound 6 is firstly isolated from A. arguta.

A new nor-sesquiterpene glycoside from Corydalis edulis / 中国中药杂志

This study is to investigate the chemical constituents from the whole plant Corydalis edulis. The chemical constituents were separated and purified by macroporous resin D101, silica gel, Sephadex LH-20, ODS, and semi-preparative HPLC. Their structures were determined by physicochemical properties and spectroscopic data. Four compounds were isolated from the dichloromethane and water extracts of the whole plant C. edulis, and identified as 6'-β-D-xylosylicariside B2(1),(3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one(2), loliolide(3), and 5,5'-dimethoxybiphenyl-2,2'-diol(4), respectively. Compound 1 is a new compound, of which the absolute configuration was established by electronic circular dichroism(ECD) calculations. Compound 4 is obtained from the plants of Papaveraceae family for the first time. Compounds 2 and 3 are firstly isolated from the Corydalis genus.

Ochracines A-E, chamigrane-related norsesquiterpene derivatives from the basidiomycete Steccherinum ochraceum HFG119.

Ochracines A-E, five previously undescribed norsesquiterpenes featured by unusual scaffolds biogenetically related to chamigrane, were isolated from the cultures of Steccherinum ochraceum. Ochracines A (1) and B (2) represent the first examples of norsesquiterpenes with an unprecedented 1,2-6,7-diseco-1,8-cyclochamigrane scaffold. Ochracines C-D (3-5) possess an unusual 1,2-6,7-diseco-chamigrane skeleton. Their structures were elucidated by analysis of spectroscopic data. The absolute configuration of ochracine A (1), and the relative configuration of ochracine B (2) were determined by ECD and/or NMR calculations. The biosynthetic pathways for the norsesquiterpenes were proposed. All isolates were evaluated for their cytotoxicity against the five human cancer cell lines HL-60, SMMC-7721, A549, MCF-7, and SW-480.

Trichobisabolins A-H, eight new bisabolane derivatives from the marine-alga-epiphytic fungus Trichoderma asperellum Y6-2.

Eight new bisabolane derivatives, trichobisabolins A-H, along with two known ones, (3R,6R,7R)-1,10-bisaboladien-3-ol (9) and (3R,6R,7S)-1,10-bisaboladien-3,6-diol (10) were isolated from the culture of Trichoderma asperellum Y6-2, obtained from the surface of the marine red alga Chondrus ocellatus. Their structures and relative configurations were identified by interpretation of 1D/2D NMR and MS data. Compounds 1-8 were assayed for inhibiting the growth of some marine-derived organisms, including four marine phytoplankton species, one marine zooplankton species, and five pathogenic bacteria. All of them exhibited inhibition against the marine phytoplanktons with IC50 values ranging from 2.1-78 µg/mL, compounds 4 and 8 showed weak lethality to the marine zooplankton, and none of them had inhibition against the five pathogenic bacteria.

Two new terpenoids from Kalimeris indica.

A new nor-sesquiterpene kalimeristone A (1), a new nor-triterpenoid kalimerislactone B (2) and eight known compounds 7-hydroxy-4'methoxyisoflavone (3), episyringaresinol (4), epipinoresinol (5), rhamnetin (6), vanillin (7), p-hydroxybenzaldehyde (8), syringic acid (9) and 3, 4-dihydroxybenzaldehyde (10) were isolated from the herbs of Kalimeris indica. The structures of these compounds were elucidated using spectroscopic techniques, such as NMR and MS. All of the compounds were isolated from this genus for the first time. The cytotoxicities against four cancer cell lines were evaluated in vitro, but were inactive.

A new norsesquiterpene from the roots of Polyalthia laui.

One new norsesquiterpene polyalone A (1), and one new natural product 9-keto-cyclocolorenone (2), along with three known analogues (3-5) were isolated from the roots of Polyalthia laui. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. All compounds were evaluated for their cytotoxic activities and antibacterial activities.

Cytotoxic sesquiterpenes from the endophytic fungus Pseudolagarobasidium acaciicola.

Twenty previously unknown compounds and two known metabolites, merulin A and merulin D, were isolated from the endophytic fungus Pseudolagarobasidium acaciicola, which was isolated from a mangrove tree, Bruguiera gymnorrhiza. Structures of the 20 compounds were elucidated by analysis of spectroscopic data. The absolute configuration of seven of these compounds was addressed by a single crystal X-ray analysis using CuKα radiation and an estimate of the Flack parameter. Three compounds also possessed a tricyclic ring system. Terpene endoperoxides isolated exhibited cytotoxic activity, while those without an endoperoxide moiety did not show activity. The endoperoxide moiety of sesquiterpenes has significant impact on cytotoxic activity, and thus is an important functionality for cytotoxicity. One terpene endoperoxide displayed potent cytotoxic activity (IC50 0.28µM), and selectively exhibited activity against the HL-60 cell line.

Wilfordonols A-D: four new norsesquiterpenes from the leaves of Tripterygium wilfordii.

Four new norsesquiterpenes wilfordonols A-D (1-4), along with three known compounds, sarmentol B (5), boscialin (6), and (+)-loliolide (7), were isolated from the leaves of Tripterygium wilfordii Hook.f.. The structures of the new compounds were elucidated on the basis of their spectroscopic analysis, and the absolute configuration of the compounds was confirmed by CD and modified Mosher's method. At a concentration of 10 µM, compounds 4, 6, and 7 inhibited signal transducer and activator of transcription 1 translocation by 34.27 ± 1.02%, 48.93 ± 1.76%, and 70.31 ± 2.20%, respectively.