[A new xanthone from hulls of Garcinia mangostana and its cytotoxic activity].

Eight compounds were isolated from ethyl acetate fraction of 80% ethanol extract of the hulls of Garcinia mangostana by silica gel, Sephadex LH-20 column chromatography, as well as prep-HPLC methods. By HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the eight compounds were identified as 16-en mangostenone E(1), α-mangostin(2), 1,7-dihydroxy-2-(3-methy-lbut-2-enyl)-3-methoxyxanthone(3), cratoxyxanthone(4), 2,6-dimethoxy-para-benzoquinone(5), methyl orselinate(6), ficusol(7), and 4-(4-carboxy-2-methoxyphenoxy)-3,5-dimethoxybenzoic acid(8). Compound 1 was a new xanthone, and compound 4 was a xanthone dimer, compound 5 was a naphthoquinone. All compounds were isolated from this plant for the first time except compounds 2 and 3. Cytotoxic bioassay suggested that compounds 1, 2 and 4 possessed moderate cytotoxicity, suppressing HeLa cell line with IC_(50) va-lues of 24.3, 35.5 and 17.1 µmol·L~(-1), respectively. Compound 4 also could suppress K562 cells with an IC_(50) value of 39.8 µmol·L~(-1).

Triterpenoids from the fruits of Aphanamixis polystachya and their inhibitory activities on nitric oxide production.

Nineteen triterpenoids, including five previously unknown (four triucallane-type derivatives and one highly oxidized A, B-seco limonoids), together with fourteen known triterpenoids, were isolated from the fruits of Aphanamixis polystachya. Their structures were elucidated by extensive spectroscopic analysis. All isolates were evaluated their anti-inflammatory activities. The result showed that all compounds inhibit LPS-induced nitric oxide production in RAW264.7 macrophages with their IC50 value ranging from 95 to 1332 uM, and compound 6 exhibited obvious anti-inflammatory activity comparable to that of the positive control, with IC50 values of 94.96 uM.

[Chemical constituents from Salacia polysperma].

Nine compounds were isolated from the 90% ethanol extract of Salacia polysperma by silica gel, Sephadex LH-20 column chromatography, together with preparative HPLC methods. Based on HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the nine compounds were identified as 28-hydroxy wilforlide B(1), wilforlide A(2), 1ß,3ß-dihydroxyurs-9(11),12-diene(3),(-)-epicatechin(4),(+)-catechin(5),(-)-4'-O-methyl-ent-galloepicatechin(6), 3-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)propan-1-one(7),(-)-(7S,8R)-4-hydroxy-3,3',5'-trimethoxy-8',9'-dinor-8,4'-oxyneoligna-7,9-diol-7'-aldehyde(8), and vanillic acid(9). Compound 1 is a new oleanane-type triterpene lactone. Compounds 1, 3, 4, 7-9 were isolated from the Salacia genus for the first time. All compounds were assayed for their α-glucosidase inhibitory activity. The results suggested that compound 8 exhibited moderate α-glucosidase inhibitory activity, with an IC_(50) value of 37.2 µmol·L~(-1), and the other compounds showed no α-glucosidase inhibitory activity.

Characterization of the complete chloroplast genome of Dendrobium christyanum and its phylogenetic analysis.

Dendrobium christyanum H.G. Reichenbach (Orchidaceae) is used as a source of the Chinese traditional medicine. Here, we report that the complete chloroplast (cp) genome sequence of D. christyanum is 157972 bp in length with134 genes, of which 114 are unique genes (80 protein-coding genes, 30 tRNAs, and 4 rRNAs). Phylogenetic analysis indicated that D. christyanum was closely related to D. strongylanthum, and D. longicornu. The newly sequenced cp genome will be useful for the phylogenetic and genetic conservation studies of Dendrobium.

Sesquiterpenoids from the roots and rhizomes of Valeriana amurensis and their effects on NGF-induced neurite outgrowth in PC12 cells.

Two new sesquiterpenoids, including a kessane-type sesquiterpenoid (1) and one bisabolane derivative (2), together with fourteen known sesquiterpenoids (3-16), were isolated from the roots and rhizomes of Valeriana amurensis. The structures of new compounds were established on the basis of extensive spectroscopic analysis. All isolates were evaluated for their effects on nerve growth factor (NGF)-mediated neurite outgrowth in pheochromocytoma (PC12) cells. As a results, four compounds including 10-12 and 15 showed potent promoting effects at the concentration of 10 µM on NGF-induced neurite outgrowth in PC12 cells with the differentiation rate of 11.84%, 12.21%, 13.77% and 12.16%, respectively.

Melotenuines A-E, cytotoxic monoterpenoid indole alkaloids from Melodinus tenuicaudatus.

Five new monoterpenoid indole alkaloids, melotenuines A-E (1-5), along with 18 known indole alkaloids, were isolated from the twigs and leaves of Melodinus tenuicaudatus. The structures of the new alkaloids were determined by a combination of MS, NMR and ECD analysis. Melotenuine A (1) represents the first example of aspidosperma-meloscandonine type bisindole alkaloids characterized by a methylene bridge between the two monomers, while melotenuine B (2) possessed a rare eburnamine-melsocandonine skeleton. All of the new indole alkaloids were evaluated for in vitro cytotoxicities against five human cancer cell lines. Among them, alkaloid 4 showed specific cytotoxicity against HL-60 cell line with IC50 value (5.15 ±â€¯0.16 µM) comparable with that of positive control.

Four new monoterpenoids from the whole plants of Valeriana stenoptera.

Four new monoterpenoids, including two new acyclic monoterpenoids (2R, 6R)-2, 6-dimethyl-8-isovaleroxyoctan-1-ol (1) and (2S, 6S)-2, 6-dimethyl-8-isovaleroxyoctan-1-ol (2), as well as two new iridoids stenopterins F-G (3 and 4), together with fifteen known compounds (5-19), were isolated from whole dried material of Valeriana stenoptera. Stenopterin F was the first reported iridoids with n-butoxyl in the Valerianaceae family. The structures of new compounds were established on the basis of extensive spectroscopic analysis.

Cytotoxic indole alkaloids from the fruits of Melodinus cochinchinensis.

Eight indole alkaloids, melosines A-H, together with 13 known alkaloids, were isolated from the fruits of Melodinus cochinchinensis. The structure elucidation of isolated secondary metabolites was based on comprehensive spectroscopic data analysis. Melosine B showed moderate cytotoxic activity against five human cancer cell lines, HL-60, SMMC-7721, A-549, MCF-7, and SW480 with IC50 values ranging from 1.6 to 8.1µM.

Bioactive Limonoid Constituents of Munronia henryi.

Fourteen new limonoids, munronins A-N (1-14), and eight known limonoids (15-22) were isolated from the whole plants of Munronia henryi. The structures of the new compounds were elucidated by 2D NMR spectroscopy and mass spectrometry, and the structure of 8 was confirmed by single-crystal X-ray diffraction analysis. Compound 1 represents the first limonoid found with a novel 7-oxabicyclo[2.2.1]heptane moiety produced by incorporating C-11 and C-14 via an oxygen atom. All compounds were evaluated for their anti-tobacco mosaic virus (TMV) activity and in vitro cytotoxicity against the human cancer HL-60, SMMC-7721, A-549, MCF-7, and SW-480 cell lines. Among them, compounds 2, 8, 9, 10, 11, 12, 18, and 20 showed significant anti-TMV activity, with IC50 values in the range 19.6-44.4 µg/mL. Compounds 1 and 18 exhibited cytotoxic effects for all five cancer cell lines, with IC50 values between 0.4 and 4.8 µM.

Antimicrobial Constituents of the Mature Carpels of Manglietiastrum sinicum.

Seven new compounds, including a eupodienone-type lignan (1), a dibenzocyclooctadiene-type lignan (2), three tetrahydrofuran-type lignans (3-5), and two 1-phenylbutyl benzoates (6, 7), together with six known compounds, were isolated from the mature carpels of Manglietiastrum sinicum. The structures of new compounds 1-7 were defined by spectroscopic techniques, and the absolute configuration of manglisin A (1) was determined by X-ray crystallography. Compounds 1-4 exhibited moderate antimicrobial activities (MIC values: 0.016-0.14 µM) against Staphylococcus aureus, MRSA 82(#), MRSA 92(#), MRSA 98(#), and MRSA 331(#). Compounds 2 and 3 showed weak cytotoxic activity against five human tumor cell lines.

Phragmalin limonoids from the stem barks of Chukrasia tabularis var. velutina.

Seven new phragmalin limonoids, chukvelutilides I-O (1-7), were isolated from the stem barks of Chukrasia tabularis var. velutina. Their structures were elucidated by extensive spectroscopic analysis. Among them, compound 1 showed moderate lethal activity against brine shrimp larvae, with an LC50 value of 84.1 µM.

Cytotoxic eburnamine-aspidospermine type bisindole alkaloids from Bousigonia mekongensis.

Four new eburnamine-aspidospermine type bisindole alkaloids, namely, mekongenines C-F (1-4), along with 27 known indole alkaloids were isolated from the twigs and leaves of Bousigonia mekongensis. Their structures with the absolute configurations were elucidated by spectroscopic methods and ECD analyses. All new compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Alkaloids 1-4 exhibited inhibitory effects with IC50 values comparable to those of cisplatin.

Limonoids from the fruits of Cipadessa cinerascens.

A new limonoid, 3-de(2-methylbutanoyl)-3-propanoylcipadesin (1), along with 10 known limonoids and 1 known triterpenoid, was isolated from the fruits of Cipadessa cinerascens. Their structures were elucidated on the basis of spectroscopic analysis. All compounds were evaluated for their antimicrobial activities, and compounds 6 and 12 showed weak antimicrobial activities against MRSA 82(#) and MRSA 92(#).

Angustifonines A and B, cytotoxic bisindole alkaloids from Bousigonia angustifolia.

Two new bisindole alkaloids, angustifonines A (1) and B (2), comprising the union of a rearranged monoterpenoid quinoline and an aspidospermine alkaloid, as well as 27 known indole alkaloids were isolated from the twigs and leaves of Bousigonia angustifolia. Their structures and absolute configurations were elucidated by a combination of MS, NMR, and computational methods. Angustifonines A and B exhibited cytotoxicity against various human cancer cell lines with IC50 values of 2.71-16.22 µM. A possible biosynthesis pathway toward the new bisindole alkaloids 1 and 2 is presented.

Limonoids from Aphanamixis polystachya and their antifeedant activity.

Eight new aphanamixoid-type aphanamixoids (C-J, 1-8) and six new prieurianin-type limonoids, aphanamixoids K-P (9-14), along with 10 known terpenoids were isolated from Aphanamixis polystachya, and their structures were established by spectroscopic data analysis. Among the new limonoids, 13 compounds exhibited antifeedant activity against the generalist Helicoverpa armigera, a plant-feeding insect, at various concentration levels. In particular, compounds 1, 4, and 5 showed potent activities with EC50 values of 0.017, 0.008, and 0.012 µmol/cm(2), respectively. On the basis of a preliminary structure-activity relationship analysis, some potential active sites in the aphanamixoid-type limonoid molecules are proposed.

Chemical constituents from Aphanamixis grandifolia.

Four new terpenoids, nemoralisins D-G (1-4), were isolated from the leaves and stems of Aphanamixis grandifolia, along with two known diterpenoids, nemoralisin C and nemoralisin. Among them, compound 1 is the first example of norsesquiterpenoid with δ-lactone moiety, and nemoralisins E-G (2-4), are a class of acyclic diterpenoids, which are structurally related nemoralisin C and nemoralisin. These structures were established on the basis of spectroscopic methods and the absolute configuration of 1 was determined by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. Nemoralisins D-G (1-4) were tested for their cytotoxicities on HL-60, SMMC-7721, A-549, MCF-7, and SW480 human tumor cell lines (IC50>40 µM), as well as the antimicrobial activities on Staphylococcus aureus, Pseudomonas aeruginosa, MRSA92(#) and MRSA98(#) (MIC>50 µg/mL).

Anti-HIV active daphnane diterpenoids from Trigonostemon thyrsoideum.

Sixteen daphnane diterpenoids, trigothysoids A-P, along with 15 known ones, were isolated from the methanol extract of the twigs and leaves of Trigonostemon thyrsoideum. Their structures were established by extensive spectroscopic techniques, including 2D NMR spectroscopy and mass spectrometry. The anti-HIV-1 activity of the compounds was also evaluated in vitro, and five compounds demonstrated potent anti-HIV-1 activity, with EC50 values of 0.015-0.001 nM and TI values of 1618-17,619.

New steroids and sesquiterpene from Turraea pubescens.

Four new compounds, including three new steroids (1-3) and one new sesquiterpene (6), and two new natural products (4-5), as well as three known steroids (7-9) were isolated from the twigs of Turraea pubescens. Compounds 3-5 are C22 steroids isolated from the Meliaceae family for the first time. Their structures were elucidated by extensive NMR and MS analyses. Compound 1 exhibited inhibitory activity against lipopolysaccharide (LPS) induced nitric oxide (NO) production in RAW264.7 cells with an IC50 value of 11.5 µM.

A new Amaryllidaceae alkaloid from the bulbs of Lycoris radiata.

AIM: To study the Amaryllidaceae alkaloids of the bulbs of Lycoris radiata. METHODS: The chemical constituents were isolated and purified by various chromatographic techniques, and the chemical structures were elucidated on the basis of spectroscopic methods. In addition, the antiviral activities of alkaloids 1-10 were evaluated using flu virus A. RESULTS: One new homolycorine-type alkaloid 2α-methoxy-6-O-ethyloduline (1), together with nine known alkaloids 2α-methoxy-6-O-methyloduline (2), trispherine (3), 8-O-demethylhomolycorine (4), homolycorine (5), 9-O-demethylhomolycorine (6), oduline (7), lycorenine (8), 6α-O-methyllycorenine (9) and O-ethyllycorenine (10) were obtained. CONCLUSION: Alkaloid 1 is a new compound, and 1-3 were major alkaloids in this plant. Alkaloids 1-3 showed weak antiviral activities against flu virus A with IC50 values of 2.06, 0.69, and 2.71 µg·mL-1 and CC50 values of 14.37, 4.79, and 80.12 µg·mL-1, respectively.

Bioactive limonoid and triterpenoid constituents of Turraea pubescens.

Eleven new limonoids, turrapubins A-K (1-11), and three new triterpenoids (12-14), along with 14 known compounds, were isolated from the twigs of Turraea pubescens. The structures of 1-14 were elucidated on the basis of NMR and MS analysis. Compounds 12, 16, 18, and 19 exhibited inhibitory activities against lipopolysaccharide-induced nitric oxide production in RAW264.7 cells. In addition, compounds 2, 11, 18, and 26 exhibited inhibitory activities against brine shrimp larvae (Artemia salina) at 100 ppm with the corrected mortality ranging from 81.7% to 100%.