A New Tetranortriterpenoid from Munronia delavayi

A tetranortriterpenoid, named munronin G, was isolated from Munronia delavayi （Meliaceae） by chromatography. Its structure was determined on the basis of 1D-, 2D-NMR and mass spectral analyses.     

Aphanalides A–H,ring A-seco limonoids from the fruits of Aphanamixis polystachya

Eight new ring A-seco limonoids, aphanalides A–H (1–8) were isolated from the fruits of Aphanamixis polystachya. Aphanalides A–C (1–3) are the first examples of ring A-seco limonoids with an unusual oxetane ring between C-7 and C-14. The structures of aphanalide A (1) and aphanalide C (3) were confirmed by single-crystal X-ray studies. Their structures including absolute stereochemistry were established on the basis of extensive NMR spectroscopic analysis, by comparison of experimental and calculated electron circular dichroism (ECD) and by X-ray diffraction, representing the first report of assignment of absolute configuration of such type ring A-seco limonoids. The biogenetic origin of aphanalides A–D (1–4) from aphanalides E–H (5–8) was also postulated.     

Ivorenoids A–F: limonoids from Khaya ivorensis

Six new limonoids, ivorenoids A–F (1–6), along with ten known analogues, were isolated from an ethanolic extract of the stems of Khaya ivorensis. Their structures were elucidated on the basis of spectroscopic analyses. Compounds 1 and 2 possessed a rare rearranged skeleton of khayanolides and a unique γ-lactone (C-16/C-8) replacing the common and characteristic δ-lactone D-ring (C-16/C-17) of limonoids. A mechanism of the interesting deuteration of H-2 and H-15β of 1, and H-15β of the solvent CD₃OD due to the keto–enol tautomerism was demonstrated. Compounds 3 and 6 showed moderate activity against HL-60 cell line with IC₅₀ values of 15.3 and 17.5 μM, respectively.     

Toonapolyynes A–D,new polyynes from Toona ciliata

Abstract

Phytochemical investigation on the leaves and twigs of Toona ciliata has led to the isolation of four new polyynes (1–4) and two knowns (5 and 6). Their structures were determined by extensive spectroscopic analysis (MS, UV, IR, and NMR) and Mosher’s method. All compounds were evaluated for their inhibitory activities against HepG2 human tumor cell line but were inactive.     

Trichiliasinenoids A–C,three 6,7-secomexicanolide limonoids with a 7,29-linkage from Trichilia sinensis

Trichiliasinenoids A–C (1–3), three new limonoids with an unprecedented C-29-C-7 connecting carbon skeleton formed by migration of C-7 from C-6 to C-29 of a mexicanolide-type limonoid precursor were isolated from the leaves and twigs of Trichilia sinensis. Their structures were assigned by spectroscopic analysis, and the absolute configurations were determined by X-ray crystallography (1) and ECD calculation (2 and 3). A possible biosynthetic pathway of 1 was also proposed. Compound 2 exhibited moderate cytotoxicity against HL-60 cells and weak cytotoxicity against SMMC-7721cells.     

Voacalgines A–E,new indole alkaloids from Voacanga grandifolia

Five new indole alkaloids, voacalgines A–E (1–5) consisting of a C-mavacurine type of skeleton with 2,3-dihydroxybenzoate moiety, a macroline-type of skeleton, or a macroline-type of skeleton with C₆ unit, were isolated from the bark of Voacanga grandifolia. Their relative structures were determined by means of NMR data. Voacalgine A showed moderate cell growth inhibitory activities against HL-60 and HCT116 cells.     

Rubischumanins A–C,new cytotoxic cyclopeptides from Rubia schumanniana

Three new cyclic hexapeptides, designated as rubischumanins A–C (1–3), together with three known ones (4–6) were isolated from the roots and rhizomes of Rubia schumanniana. The structures were elucidated on the basis of extensive spectroscopic analysis. Cytotoxicity of these compounds was evaluated and compounds 1, 2, 4, and 5 showed cytotoxicity against A549, BGC-823, and Hela cell lines.     

Fluevirines A–D,four new securinega-type alkaloids from Flueggea virosa

Four new securinega-type alkaloids, fluevirines A–D (1–4), along with ten known ones, were isolated from the twigs and leaves of Flueggea virosa. The structures of the new ones were elucidated by means of spectroscopic methods, and their absolute configurations were assigned by CD spectra. Among them, fluevirine A (1) was a novel C,C-linked dimeric indolizidine alkaloid and showed weak antimicrobial activity against Staphylococcus aureus.     

A new triterpenoid from Alisma orientalis

A new triterpenoid,named 11,25-aahydro-alisol E was isolated from the rhizomes of Alisma orientalis together with nine known compounds.Their structures were elucidated by spectroscopic methods.Some compounds showed weak anti-tumor activities in cytotoxic experiments.     

A new ellagitannin from Cleidion bracteosum

A new ellagitannin, named bractin (1), had been isolated from the dried aerial part of Cleidion bracteosum. Its structure was determined based on various of spectral analysis.     

A new xanthene from Blumea riparia

A new xanthene, named blumeaxanthene, was isolated from Blumea riparia DC. The structure was elucidated on the basis of the data of NMR, MS, IR.     

A new Furostanoside from Asparagus filicinus

A new furostanoside,aspafiliosde D(1) has been isolated from the root of Asparagus filicinus.Its structure was determined by spectral and chemical methods.     

A new sesquiterpene from Caragana intermediia

A new alloaromadendrane-type sesquiterpene,(-)-alloaromadendrane-3β,9β-diol(1),has been isolated from the aerial part of Caragana intermediia.The structure of (-)-alloaromadendrane-3β,9β-diol(1)was established by spectroscopic methods, including X-ray analysis that provided its relative stereochemistry.Bioassay showed that (-)-alloaromadendrane-3β,9β-diol (1)possesses anti-pyricularia oryzae P-2b activity with MIC value of 10μg/mL.     

A new iridoid from Incarvillea delavayi

A new iridoid was isolated from the 80% ethanol extract of the whole plant of Incarvillea delavayi. Its structure was defined, and named incarvillic acid, on the basis of spectral evidences.     

A new tetrastilbene from Caragana sinica

A new tetrastilbene named carasinol D （1） was isolated from the roots of Caragana sinica. Its structure was elucidated by spectroscopic analysis. Compound 1 was obtained from carasinol B （2） by an acid-catalyzed conversion.     

A new alkaloid from Stemona sessilifolia

A new alkaloid, named sessilistemonamine D, was isolated from the roots of Stemona sessilifolia and the structure and relative configuration were determined on the basis of NMR and MS spectrometric data analysis.     

Tubakialactones A–E,new polyketides from the endophytic fungus Tubakia sp. ECN-111

Three new isocoumarins and two new phthalides, tubakialactones A–E (1–5), together with three known polyketides including (R)-3,4-dihydro-4-hydroxyl-6,8-dimethoxy-4-methyl-3-methylene-1H-2-benzopyran-1-one (6), (?)-5,7-dimethoxy-3-methyl-1(3H)-isobenzofuranone (7), and isosclerone (8) were found in the endophytic fungus Tubakia sp. ECN-111 isolated from the leaves of Houttuynia cordata. The chemical structures of the new compounds were determined by spectroscopic analyses, including extensive 2D-NMR experiments. The absolute configuration of 3 and 7 was determined by optical rotation and circular dichroism.     

Artanomadimers A–F: six new dimeric guaianolides from Artemisia anomala

A novel dimeric guaianolide with an unprecedented skeleton, named artanomadimer A (1), and five new analogues, artanomadimers B–F (2–6), were isolated from the aerial parts of Artemisia anomala. Their structures and stereochemistry were elucidated by extensive spectroscopic methods, and the absolute stereochemistry of compound 4 was confirmed by X-ray crystallographic analysis. Artanomadimer A (1) is probably formed through a Diels–Alder reaction with the new carbon–carbon bond formation of C-11/C-2′ and C-13/C-5′ based on its structure. A cytotoxic evaluation showed that compounds 1 and 6 exhibited significant inhibitory effects against the cell growth of BGC-823 tumor cell lines with IC₅₀ values of 2.71 and 6.25 μM, respectively.     

Briaviodiols B–E,new anti-inflammatory hydroperoxyfurancembranoids from Briareum violaceum

Four new hydroperoxyfurancembranoids, briaviodiols B–E (1–4), were obtained from an octocoral identified as Briareum violaceum. The structures of cembranoids 1–4 were established by using spectroscopic methods and comparing the spectroscopic data with those of known related analogues. Compounds 1, 3, and 4 were found to exhibit significant in vitro anti-inflammatory activity in LPS-induced RAW 264.7 macrophage cells by inhibiting the expression of iNOS protein.     

A new isoflavonolignan from Pueraria alopecuroides Craib

A new isoflavonolignan has been isolated from the Pueraria alopecuroides Craib. The structure was elucidated by the combination of 1D, 2D NMR analysis and mass spectrometry.