Stilbenoids and Phenols in Acanthopanax brachypus

Three new stilbenoids, including α‐(3′‐O‐β‐D ‐glucopyranosyl‐5′‐methoxyphenyl)‐2‐methoxy‐3‐methylbenzofuran ( 1 ), 4‐methyl‐(E)‐resveratrol 3‐(2″‐p‐hydroxybenzoyl)‐O‐β‐D ‐glucopyranoside ( 2 ), and 5‐O‐methyl‐(E)‐resveratrol 3‐(6″‐acetyl)‐O‐β‐D ‐glucopyranoside ( 3 ), together with six known stilbenoids and phenols, acetovanillone 1‐(6′‐vanilloyl)‐O‐β‐D ‐glucopyranoside, eugenyl‐O‐β‐D ‐glucopyranoside, α‐(3′‐hydroxy‐5′‐methoxy‐2′‐methylphenyl)‐2‐hydroxybenzofuran, α‐(3′‐hydroxy‐5′‐methoxyphenyl)‐2‐hydroxybenzofuran, pinosilvin 3‐O‐β‐D ‐glucopyranoside, and (E)‐resveratrol 3‐(6″‐galloyl)‐O‐β‐D ‐glucopyranoside were isolated from the EtOH extract of the stem bark of Acanthopanax brachypus. Their structures were determined by spectral analysis including extensive 2D‐NMR spectral analyses. Compounds 2 and 3 exhibited weak cytotoxicity against human tumor A549 cell line (IC₅₀ values of 4.87 and 5.63 μM , resp.).     

Antitumor activity of stilbenoids and flavonoids isolated from Acanthopanax brachypus

This report is the first to detail the antitumor activity of Acanthopanax brachypus, a species well recognized by eastern folk medicine. Four stilbeniods and nine flavonoids have been isolated from stem bark of the plant. The isolates have been tested for their antitumor activity against selected human cancer cell lines (HgpG-2, MCF-7, K-562, and A-549). Even though three of the compounds have shown high to moderate cytotoxicity against certain cell lines (IC₅₀ of 4.5 to 6.5 μg/mL), in most of the experiments little or no anticancer activity has been revealed.     

刺五加叶中黄酮类化合物的结构鉴定

利用电喷雾质谱发现刺五加叶中存在4种黄酮类化合物,进一步分离得到其中的两种,经核磁质谱鉴定,一种为槲皮甙(槲皮素－3－O－α－L－鼠李糖),另一种为金丝桃甙(槲皮素－3－O－β-D－半乳糖).其余两种难以分离的黄酮甙经电喷雾多级串联质谱分析,初步推断为槲皮素和芦丁(槲皮素－3-O－芦丁糖).以上4种均为黄酮醇类化合物,除金丝桃甙外,其它3种为刺五加叶中尚未见报道的黄酮类成分.     

Flavonoid constituents from Spiranthes australis LINDL

Chemical investigation of the whole plant of Spiranthes australis (R. BROWN) LINDL. resulted in the isolation and characterization of three new flavonoid constituents, 5-hydroxy-4'-[(2-isopentenyl)oxy]-3,7,3'-trimethoxyflavone (1), 3-O-[[O-beta-D-xylopyranosyl]-(1-->2)-beta-D-glucopyranosyl]-8-(p-hydroxy-benzyl)-kaempferol (2) and 3-O-[O-[2-O-(E)-p-coumaroyl-beta-D-xylopyranosyl]-(1-->2)-beta-D-glucopyranosyl]-8-(p-hydroxy-benzyl)-kaempferol (3), together with six known flavonoid compounds. The structures of new compounds were determined on the basis of spectroscopic analysis, including HR-ESI-MS, 1D- and 2D-NMR techniques and chemical methods.     

Phenolic constituents from the roots of Alangium chinense

Three new phenolics(1–3) and twenty-eight known compounds(4–31) were isolated from an ethanolic extract of roots of Alangium chinense. Compound 11 exhibited antiviral activity against Coxsackie virus B3 with IC50 values of 16.89 mmol/L. Compounds 1, 10–17, 19–21, and 23 showed strong antioxidant activity against Fe~(2+)-cysteine-induced rat liver microsomal lipid peroxidation, with IC_(50) values of 0.14–8.18 mmol/L.     

Chemical constituents from the roots of Xanthium sibiricum

Xanthium sibiricum patrin ex Widder (Compositae) is an annual herb which grows all around China. Chemical investigations of its roots resulted in the identification of 15 compounds: stigmast-4-en-6β-ol-3-one (1), β-sitostenone (2), β-sitosterol (3), nonadecanoic acid (4), 5α,8α-epidioxy-22E-ergosta-6,22-dien-3β-ol (5), scopoletin (6), Jatrocin B (7), (±)syringaresinol (8), 9,9'-O-di-(E)-feruloyl-(-)-secoisolariciresinol (9), cleomiscosin A (10), cleomiscosin C (11), N-trans-feruloyl tyramine (12), daucosterol (13), 5-methyluracil (14) and uracil (15). Structures were elucidated by spectroscopic (NMR and MS) methods and confirmed by comparing with reference samples and literature data. Compounds 1-2, 4-12, 14, and 15 were isolated from this genus for the first time, while this is the first report of coumarinolignoids in the Compositae family, and coumarinoligoids could be considered as valuable chemotaxonomic markers for the plant.     

Chemical constituents from roots of Taraxacum formosanum

Two new compounds, taraxafolide (1) and (+)-taraxafolin-B (2) together with eighteen known compounds, which include one sesquiterpene, thirteen benzenoids, two indole alkaloids, one pyridine derivative and steroid mixtures were isolated and characterized from the fresh roots of Taraxacum formosanum. Structures of new compounds were determined by spectral analysis. (+)-Taraxafolin-B had the bioactive caffeic acid moiety, but its activity was weaker than alpha-tocopherol in DPPH radicals scavenging activity assay.     

Anticancer constituents from the roots of Rubia cordifolia L

Activity-directed isolation of the methylene chloride fraction of the roots of Rubia cordifolia L. resulted in the identification of a new epoxymollugin (3) and eight known compounds (1, 2, 4-9). The structures of the compounds were elucidated from chemical and spectroscopic evidence. In addition, their topoisomerase I and II inhibitory activities and cytotoxicities were measured.     

Bioassay-guided isolation of antibacterial constituents from Diospyros lotus roots

The aim of this study was to explore the extract/fractions and compounds of Diospyros lotus against various Gram-positive and Gram-negative bacteria strain. The results showed marked susceptibility of extract and its fractions against test pathogens. Among them, chloroform fraction was most dominant and effective against all tested bacteria. The chloroform fraction was subjected to column chromatography which led to the isolation of lupeol (1), 7-methyljuglone (2), β-sitosterol (3), stigmasterol (4), betulinic acid (5), diospyrin (6) and 8-hydroxyisodiospyrin (7). Among the isolated compounds, betulinic acid (5) showed significant activity against most of the tested pathogen. In conclusion, our study validated the traditional uses of the plant in the treatment of infectious diseases which was also strongly supported by the isolated compound, betulinic acid (5).     

Water-soluble phenylpropanoid constituents from aerial roots of Ficus microcarpa

New water-soluble phenylpropanoid constituents, ficuscarpanoside A, guaiacylglycerol 9-O-beta-D-glucopyranoside, and erythro-guaiacylglycerol 9-O-beta-D-glucopyranoside, along with known guaiacylglycerol, erythro-guaiacylglycerol, 4-methoxy guaiacylglycerol 7-O-beta-D-glucopyranoside, and 3-(4-hydroxy-3-methoxy phenyl) propan-1,2-diol, have been isolated from the aerial roots of Ficus microcarpa. Their structures were elucidated on the basis of 1D and 2D NMR experiments.     

Chemical constituents of the roots of Piper sarmentosum

Sixteen compounds were isolated from the fresh roots of Piper sarmentosum. Seven of these have been previously isolated from the fruits and leaves of this plant: the aromatic alkene (1), 1-allyl-2-methoxy-4,5-methylenedioxybenzene (4), beta-sitosterol, pyrrole amide (6), sarmentine (10), sarmentosine (13) and pellitorine (14). (+)-Sesamin (2), horsfieldin (3), two pyrrolidine amides 11 and 12, guineensine (15) and brachystamide B (16) are new for P. sarmentosum. Sarmentamide A, B, and C (7-9) are new natural products. Compounds 1--4 and 6--16 were tested for antiplasmodial, antimycobacterial and antifungal activities.