New eudesmane sesquiterpenes from Alpinia oxyphylla and determination of their inhibitory effects on microglia.

The fruits of Alpinia oxyphylla are used as healthcare products for the protection on neurons and prevention of dementia. Two new noreudesmane sesquiterpenoids, (5R,7S,10S)-5-hydroxy-13-noreudesma-3-en-2,11-dione (1) and (10R)-13-noreudesma-4,6-dien-3,11-dione (2), and a new eudesmane sesquiterpenoid, (5S,8R,10R)-2-oxoeudesma-3,7(11)-dien-12,8-olide (3), as well as 12 known sesquiterpenoids, were isolated from the fruits of A. oxyphylla.

Two new acetylated flavonoid glycosides from Phyllanthus urinaria.

Two new acetylated flavonoid glycosides, quercetin 3-O-α-l-(2,4-di-O-acetyl) rhamnopyranoside-7-O-α-l-rhamnopyranoside (1) and quercetin 3-O-α-l-(3,4-di-O-acetyl) rhamnopyranoside-7-O-α-l-rhamnopyranoside (2), together with two known compounds, quercetin (3) and quercetin 3-O-α-l-rhamnopyranoside (4), were isolated from the ethanol extract of Phyllanthus urinaria. The structures of the new compounds were determined on the basis of extensive spectroscopic data including IR, HR-ESI-MS, 1D NMR, and 2D NMR.

[Chemical constituents of Rhododendron seniavinii].

Objective: To study the chemical constituents of Rhododendron seniavinii.

Method: Compounds were isolated from the aqueous extract of the leaves of R. seniavinii by using Sephadex LH-20, ODS open column chromatography and other means.

Two new vinblastine-type N-oxide alkaloids from Catharanthus roseus.

Two new vinblastine-type N-oxide alkaloids, 17-desacetoxyvinblastine N'b-oxide (1) and 20'-deoxyvinblastine N'b-oxide (2), were isolated from the leaves of Catharanthus roseus. The structures of 1 and 2 were established by the analysis of their nuclear magnetic resonance and HR-ESI-MS spectroscopic data. All alkaloids were evaluated for their cytotoxic activities against the human hepatocellular carcinoma (HepG2) cell line, human colorectal carcinoma (Lovo) cell line and human breast carcinoma (MCF-7) cell line by the MTT method in vitro, respectively.

α-Glucosidase inhibitory effect and simultaneous quantification of three major flavonoid glycosides in Microctis folium.

Microctis Folium, the leaves of Microcos paniculata L., is a commonly used herbal tea material. The methanol extract of Microctis Folium and its principle compounds vitexin (1), isovitexin (2) and isorhamnetin 3-O-β-D-rutinoside (3) were investigated for their α-glucosidase inhibitory effects.

Bipiperidinyl derivatives of 23-hydroxybetulinic acid reverse resistance of HepG2/ADM and MCF-7/ADR cells.

Multidrug resistance (MDR) is a major obstacle to successful chemotherapy for cancer; thus, novel MDR reversers are urgently needed. In the present study, we assessed whether two synthetic derivatives of 23-hydroxybetulinic acid, 3,23-O-diacetyl-17-1,4'-bipiperidinyl betulinic amide (DABB) and 3,23-O-dihydroxy-17-1,4'-bipiperidinyl betulinic amide (DHBB), could reverse MDR induced by ATP-binding cassette (ABC) transporters. Using the MTT assay, we found that DABB and DHBB could enhance the cytotoxicities of ABCB1 substrates doxorubicin, vincristine, and paclitaxel in ABCB1-overexpressing HepG2/ADM and MCF-7/ADR cells, whereas that of a non-ABCB1 substrate cisplatin was unaffected.

Arenobufagin, a natural bufadienolide from toad venom, induces apoptosis and autophagy in human hepatocellular carcinoma cells through inhibition of PI3K/Akt/mTOR pathway.

Hepatocellular carcinoma (HCC) is a deadly form of cancer without effective chemotherapy so far. Currently, only sorafenib, a multitargeted tyrosine kinase inhibitor, slightly improves survival in HCC patients. In searching for natural anti-HCC components from toad venom, which is frequently used in the treatment of liver cancer in traditional Chinese medicine, we discovered that arenobufagin, a bufadienolide from toad venom, had potent antineoplastic activity against HCC HepG2 cells as well as corresponding multidrug-resistant HepG2/ADM cells.

Two new glycosides from Vitex negundo.

Two new glycosides, 2-methyl pyromeconic acid 3-O-β-D-glucopyranoside-6'-(O-4″-hydroxybenzoate) (1), 6'-O-p-hydroxybenzoyl-gardoside (2) and four known iridoid glycosides (3-6) were isolated from the whole plant of Vitex negundo. Their structures were elucidated on the basis of spectroscopic methods including HR-ESI-MS, 1D and 2D NMR.

Saxifragifolin D induces the interplay between apoptosis and autophagy in breast cancer cells through ROS-dependent endoplasmic reticulum stress.

Breast cancer is the leading cause of cancer death among females, and novel chemotherapeutic drugs for treating breast cancer are needed urgently. Saxifragifolin D (SD) was isolated by our group from Androsace umbellata which is commonly used to treat solid tumor. In this study, we evaluated its growth inhibitory effect on breast cancer cells and explored the underlying molecular mechanisms.

Five new phenolic glycosides from Hedyotis scandens.

Five new phenolic glycosides, hedyotosides A-E (1-5), including a new cyanogenic glycoside (1), along with 10 known compounds (6-15) were isolated from the whole plants of Hedyotis scandens. The structures of compounds 1-5 were established by extensive spectroscopic analyses and acid hydrolysis. All the isolated compounds were evaluated for their in vitro antiviral activity against respiratory syncytial virus (RSV) with cytopathic effect (CPE) reduction assay.

[Determination of organochlorine pesticide residues in Microcos paniculata by GC].

Objective: To establish a method for determination 9 organochlorine pesticide residue in Microcos paniculata by gas chromatography.

Methods: The sample was infiltrated with water and extracted with hexane by ultrasonic. The extract solvent was purified by concentrated sulphuric acid.

Triterpenoid saponins from rhizomes of Paris polyphylla var. yunnanensis.

Phytochemical investigation of the rhizomes of Paris polyphylla var. yunnanensis resulted in the isolation of six new oleanane-type triterpenoid saponins, paritrisides A-F (1-6), along with nine known triterpenoid saponins (7-15). The structures of the new compounds were elucidated on the basis of spectroscopic analysis and acid hydrolysis.

Cytotoxic quassinoids from Ailanthus altissima.

Two new quassinoids, altissinol A (1) and B (7), together with 12 known quassinoids, were isolated from the 95% ethanol extract of the barks of Ailanthus altissima. The structures of the new compounds (1 and 7) were determined on the basis of the spectroscopic methods including UV, IR, HR-ESI-MS, 1D and 2D NMR. The cytotoxic potential of all isolates were evaluated in vitro against three human hepatoma cell lines.

[Study on the HPLC fingerprint and simultaneous determination of three triterpene glycosides in Schefflera heptaphylla].

Objective: To establish the HPLC fingerprint and simultaneously determination three triterpene glycosides in Schefflera heptaphylla.

Methods: The separation was carried out on an Agilent Zorbax SB-C18 (4.6 mm x 250 mm, 5 microm) column eluted with methanol--0.

[Chemical constituents from the aerial roots of Ficus microcarpa].

Objective: To study the chemical constituents of the aerial roots of Ficus microcarpa.

Methods: The compounds were isolated and purified by column chromatographic methods on silica gel and Sephadex LH-20. Their structures were elucidated by physicochemical properties and spectral data.

Clerodane diterpenoids from Croton crassifolius.

Seven new clerodane diterpenoids (1-7) were isolated from roots of Croton crassifolius, along with six known compounds. The structures were elucidated by extensive spectroscopic methods (IR, UV, HRESIMS, 1D NMR, and 2D NMR), and the structures of 1, 3, 4, and 7 were confirmed by single-crystal X-ray diffraction analyses. Compounds 1-13 were evaluated for in vitro antiviral activity against herpes simplex virus type 1 using the cytopathic effect reduction assay.

Amaryllidaceae alkaloids inhibit nuclear-to-cytoplasmic export of ribonucleoprotein (RNP) complex of highly pathogenic avian influenza virus H5N1.

Background: Few drugs are currently licensed to treat influenza A infection, and new therapies are needed, especially for highly pathogenic strains. Traditional medicinal plants, such as Lycoris radiata, are a potential source of new antiviral agents.

Objective: To test 15 Amaryllidaceae alkaloids isolated from the bulbs of L.

Protective effects and mechanisms of curcumin on podophyllotoxin toxicity in vitro and in vivo.

Podophyllotoxin (POD) is a naturally occurring lignan with pronounced antineoplastic and antiviral properties. POD binds to tubulin and prevents the formation of mitotic spindle. Although cases of overdose or accidental ingestion are quite often, no specific therapy is currently available to treat the POD intoxication.

Cajaninstilbene acid relaxes rat renal arteries: roles of Ca2+ antagonism and protein kinase C-dependent mechanism.

Cajaninstilbene acid (CSA) is a major active component present in the leaves of Cajanus cajan (L.) Millsp. The present study explores the underlying cellular mechanisms for CSA-induced relaxation in rat renal arteries.

BBA, a derivative of 23-hydroxybetulinic acid, potently reverses ABCB1-mediated drug resistance in vitro and in vivo.

23-O-(1,4'-Bipiperidine-1-carbonyl)betulinic acid (BBA), a synthetic derivative of 23-hydroxybetulinic acid (23-HBA), shows a reversal effect on multidrug resistance (MDR) in our preliminary screening. Overexpression of ATP-binding cassette (ABC) transporters such as ABCB1, ABCG2, and ABCC1 has been reported in recent studies to be a major factor contributing to MDR. Our study results showed that BBA enhanced the cytotoxicity of ABCB1 substrates and increased the accumulation of doxorubicin or rhodamine123 in ABCB1 overexpressing cells, but had no effect on non ABCB1 substrate, such as cisplatin; what's more, BBA slightly reversed ABCG2-mediated resistance to SN-38, but did not affect the ABCC1-mediated MDR.

Guadial A and psiguadials C and D, three unusual meroterpenoids from Psidium guajava.

The first monoterpene-based meroterpenoid (1) and two novel sesquiterpene-based ones (2 and 3) with unprecedented skeletons were isolated from the leaves of Psidium guajava. Their structures with absolute configuration were elucidated by extensive spectroscopic studies. A plausible biosynthetic pathway for all meroterpenoids from the title plant is also proposed.

[Study on phenolic constituents of Amomum villosum].

Objective: To study the chemical constituents of Amomum villosum.

Methods: Compounds were isolated from the alcoholic extract using polyamide, silica gel, Sephadex LH-20, ODS open column chromatography and other means. Their structures were elucidated according to spectral data and physiochemical properties.

Two pregnane derivatives and a quinolone alkaloid from Helicteres angustifolia.

Phytochemical investigation of the ethanol extract from roots of Helicteres angustifolia led to the isolation of two new pregnane derivatives, heligenin A-B (1-2), and a new quinolone alkaloid, helicterone A (3), along with thirteen known compounds (4-16). The structures of new compounds were established by analysis of extensive spectroscopic data. The absolute configuration of 1 was determined by application of the modified Mosher's method.

New steroidal saponins and sterol glycosides from Paris polyphylla var. yunnanensis.

Four new steroidal saponins, pariposides A-D (1-4), and two new sterol glycosides, pariposides E-F (5-6), along with eight known steroidal saponins (7-14), two known sterol glycosides (15-16), and two known ecdysteroids (17-18), were isolated from the roots of Paris polyphylla var. yunnanensis. Among them, compounds 1-4 are the first spirostanol saponins with a peroxy group located between C-5 and C-8 of the aglycone.

[Chemical constituents from the fruits of Areca catechu].

Objective: To investigate the chemical constituents of the fruits of Areca catechu.

Methods: The chemical constituents were isolated by silica gel, RP-18 and Sephadex LH-20 column chromatographies. Their structures were determined by chemical and spectroscopic methods.