Racemic 3,4-dihydro-4-naphthyl-naphthalen-1(2H)-ones from Juglans regia flowers.

Three previously undescribed (±)-3,4-dihydro-4-naphthyl-naphthalen-1(2H)-one derivatives were isolated from Juglans regia flowers. Elucidation of the 2D structures of these first-reported compounds was completed via regular spectroscopic methods. The assignment of racemic nature of these compounds was achieved using the examination of their chiral HPLC profiles. (±)-2,3-Dihydro-4',8,8'-trihydroxy-(1,1'-binaphthalen)-4(1H)-one, (±)-2,3-dihydro-4',5,8,8'-tetrahydroxy-(1,1'-binaphthalen)-4(1H)-one, and (±)-2,3-dihydro-1',5,5',8-tetrahydroxy-(1,2'-binaphthalen)-4(1H)-one were the structures of these racemic compounds, all taking on central chirality. The resolution of all the racemic compounds was conducted and achieved using a chiral HPLC procedure. The absolute configurations of the three isolated pairs of enantiomers were assigned via time-dependent density functional theory calculations from the electronic circular dichroism data. The findings in this paper demonstrated that the relevant biochemical reactions for the construction of these 3,4-dihydro-4-naphthyl-naphthalen-1(2H)-one derivatives in the test plant are nonselective. The (±)-2,3-dihydro-4',8,8'-trihydroxy-(1,1'-binaphthalen)-4(1H)-one showed selective inhibitory activity on tumor cells growth, preliminarily supporting the application of Juglans regia flowers to protect against cancers in a few Chinese folk areas.

Sugar-free pregnane-type steroids from the roots of Cynanchum stauntonii.

Two new sugar-free 14,15-secopregnane-type steroids, 14-O-methyl-3-epi-hirundigenin (1) and 2-deoxyamplexicogenin A (2), along with two known sugar-free pregnane-type steroids, were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii. The structures of the new compounds were characterized on the basis of extensive spectroscopic analyses, mainly 1D and 2D NMR methods, albeit the MS experiments did not display the molecular ion peaks. Compound 2 was the aglycones of stauntosides J and K, etc., previously isolated from C. stauntonii. The isolation and identification of the new compounds graced the structural diversity of pregnane-type steroids from C. stauntonii.

[Lignans from cultivated Gynura nepalensis].

Taking application of some isolation and purification technologies, including solvent extraction, rude solvent isolation, column chromatographies on silica gel and Sephadex LH-20 , and preparative HPLC , 4 compounds were obtained from Gynura nepalensis cultivated in a suburban area of Beijing. Their structures were identified by spectroscopic methods in conjunction with comparison of the NMR data with literature values as 7S,8R-9'-O-ethyl-dehydrodiconiferyl-9-acetate (1), 9'-O-ethyl-dehydrodiconiferyl alcohol (2), dehydrodiconiferyl-9,9'-diacetate(3), and (+)-medioresinol(4), respectively. 1 is a new 2,3-dihydrobenzofuran-8,3'-neolignane type compound, and 2-4 were isolated from G.nepalensis for the first time. The complete assignment of the 1H- and 13C-NMR spectroscopic data of the four compounds recorded in DMSO-d6 was achieved.

Phenylpropanoids from the stems of Ephedra sinica.

Two new compounds of phenylpropanoids, (S)-N-((1R,2S)-1-hydroxy-1-phenylpropan-2-yl)-5-oxopyrrolidine-2-carboxamide (1) and (3R)-3-O-ß-d-glucopyranosyl-3-phenylpropanoic acid (2), were isolated from the stems of Ephedra sinica. Their structures were elucidated by in-depth examination of spectroscopic data, mainly including those from the 1D and 2D NMR and HRESIMS techniques, and chemical method. The absolute configurations of the two compounds were also corroborated through CD procedure.

Two new flavonoids from the roots of Scutellaria baicalensis.

One new flavone, 5,7-dihydroxy-8,2',3',6'-tetramethoxyflavone (1), and one new flavonol, 5,7,6'-trihydroxy-2'-methoxyflavonol (2), were isolated from the roots of Scutellaria baicalensis, and their structures were elucidated on the basis of extensive spectroscopic evidences, especially 1D and 2D NMR and HR-ESI-MS experiments. The structure features of these new compounds lie in the substitution at both C-2' and C-6' positions of B-ring by hydroxyl or methoxyl groups.

[Constituents with anti-oxidative activity from seeds of Jufeng grape].

Taking application of some isolation and purification technologies, including crushing, solvent extraction, preliminary solvent isolation, column chromatographies over silica gel and Sephadex LH-20 gel and preparative HPLC, 8 compounds were obtained from the seeds of Jufeng grape sourced from market. Their structures were identified by spectroscopic methods and comparison with literature values as Catechin (1), Epicatechin (2), quercetin (3), ethylgallate (4), rel-(2S, 3R) -2-(4-hydroxy-3-methoxyphenyl) -3- (hydroxymethyl)-5-(3-hydroxypropyl)-2,3-dihydrobenzofuran-7-ol (5), rel-(2α, 3ß)-7-O-methylcedrusin (6), rel-(1R,2S)-1-(4-hydroxy-3-methoxyphenyl) -2-(4-(3-hydroxypropyl) -2-methoxyphenoxy) propane-1,3-diol (7), and (+) -isolariciresinol (8), respectively. Compounds 5-8 were serial lignans isolated from the seeds of grape for the first time. Structurally, 5 and 6 belong in benzofuran-8,3'-neolignans, 7 in 8,4'-oxyneolignan, and 8 in 8,8' :2,7'-cyclolignan. According to in vitro activity evaluation conducted in cell model, compound 6 showed significant anti-oxidative ability, with the activity of RAW264. 7 cell superoxide dismutase being raised evidently in the test as compared with the positive anti-oxidative agents, compounds 1 and 2.

[Study on chemical constituents from cultivated Gynura nepalensis].

Taking application of some isolation and purification technologies, such as solvent extraction, preliminary solvent isolation, column chromatographies over silica gel and Sephadex LH-20 gel and preparative HPLC, 10 compounds were obtained from Gynura nepalensis cultivated in the suburban area of Beijing. Their structures were identified by spectroscopic methods and comparison with literature as (3R) -3-hydroxy-ß-ionone (1), (3S,5R, 6S, 7E) -5, 6-epoxy-3-hydroxy-7-megastigmen-9-one (2), (+) -boscialin (3), 3, 6-trans-3-hydroxy-α-ionone (4), 3, 6-cis-3-hydroxy-α-ionone (5), 3, 4-cis-3, 4-dihydroxy-ß-ionone (6), ethyl caffeate (7), loliolide (8), 1H-indole-3-carbaldehyde (9), and 3-(hydroxyacetyl)indole (10), respectively. All compounds were isolated from the title plant for the first time, and with compounds 1, 2, 4-7, 9 and 10 being isolated from Gynura species for the first time. Structurally, the above compounds 1-6 belong to C13 nor-sesquiterpenoids, sharing the same carbon skeleton of megastigmane. According to this study, they are one of major kinds of chemical constituents of Gynura nepalensis and have important reference value for the investigation on phytotaxonomy of this species.

Three new steroidal glycosides from the roots of Cynanchum stauntonii.

Three new steroidal glycosides, named as stauntosides L, M, and N (1-3), along with one known C21 steroidal glycoside, anhydrohirundigenin monothevetoside (4), were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses, mainly 1D and 2D NMR, HRESI-MS, and chemical methods.

Osteoclast-inhibiting saikosaponin derivatives from Bupleurum chinense.

Five new saikosaponins, saikosaponin w (1), 21ß-hydroxysaikosaponin b2 (2), 6″-O-acetylsaikosaponin e (3), 6″-O-acetylsaikosaponin b1 (4), and 6″-O-acetylsaikosaponin b3 (5), along with twenty-two known ones (6-27), have been isolated from the roots of Bupleurum chinense. Their structures were elucidated on the basis of detailed spectroscopic analysis, including mainly 1D and 2D NMR and HRESI-MS, qualitative chemical methods, and comparison with the literatures. Osteoclast-inhibiting activity of some of the isolated compounds was evaluated in vitro, with five ones have shown significant activity by inhibitory rates ranging from 48.3% to 56.1% at the concentration of 10µM and with significant differences among groups observed.

Two new stemona alkaloids from Stemona tuberosa Lour.

Two new pyrrolo[1,2-α]azepine-type stemona alkaloids, named as tuberostemonoxirine (1) and 9α-epi-tuberospironine (2), were isolated from the roots of Stemona tuberosa. The structures and relative configurations of new compounds were established on the basis of extensive spectroscopic evidences, especially 1D and 2D NMR and HR-MS experiments.

[Advance in studies on pharmacological activity of coptisine hydrochloride].

Coptisine hydrochloride, as a natural protoberberine alkaloid quaternary ammonium salt, can be found in many species of Ranunculaceae and Papaveraceae plants. Despite no in-depth studies on coptisine hydrochloride, some literatures have reported that coptisine hydrochloride has such pharmacological activities as inhibition of monoamine oxidase of type A, selective inhibition and double inhibition against vascular smooth muscle cell proliferation, inhibition of differentiation and function of osteoclasts, selective regulation of multidrug-resistant and drug-resistant proteins in vascular smooth muscle cells, anti-fungus, protection of gastric-mucous membrane, cytotoxicity, and myocardial protection. Given to the fact of the lack of systematic review and summary of studies on coptisine hydrochloride, we summarize and analyze the study literatures on the pharmacological activity of coptisine hydrochloride published in recent years, so as to provide information for studies on new drugs of coptisine hydrochloride on the basis of the pharmacological activity.

Nine new steroidal glycosides from the roots of Cynanchum stauntonii.

Nine new steroidal glycosides, named as stauntosides C-K (2, 5, 7-10, 13, 14, and 16), along with seven known compounds (1, 3, 4, 6, 11, 12, and 15) were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses, mainly 1D and 2D NMR, and HRESI-MS, and qualitative chemical methods. Their significance in terms of the chemotaxonomy of C. stauntonii is discussed.

Two new quaternary protoberberine alkaloids from Corydalis yanhusuo.

Two new quaternary protoberberine alkaloids, namely corydayanine (1) and yanhusuine (2), were isolated from the tubers of Corydalis yanhusuo. On the basis of extensive chemical and spectroscopic evidences, especially 1D and 2D NMR and HRMS experiments, their structures were elucidated as 5,6-dihydro-3,9-dihydroxy-2,10-dimethoxy-13-methyl-dibenzo[a,g] quinolizinium alkaloid and 5,6-dihydro-12-hydroxy-2,3,9-trimethoxy-13-methyl-dibenzo[a,g] quinolizinium alkaloid, respectively.

Chemical constituents of the whole plant of Elsholtzia rugulosa.

A new lignan glycoside, 7α, 7'ß-bis-(4-hydroxy-3-methoxyphenyl)-7,9':7',9-diepoxylignan-8αH,8'α-O-ß-d-(2″,7'α-epoxy)-glucopyranoside, named elshrugulosain (1), has been isolated from the EtOH extract of Elsholtzia rugulosa, together with six known compounds, ( - )-bornyl (E)-3,4,5-trimethoxycinnamate, apigenin, luteolin, apigenin-7-O-ß-d-glucopyranoside, luteolin-7-O-ß-d-glucopyranoside, and luteolin-3'-glucuronate methyl ester. Their structures were characterized by spectroscopic methods and comparison with the data in the literature. On the basis of detailed 1D and 2D NMR spectral analysis, as well as X-ray crystallographic diffraction, the NMR spectroscopic data of ( - )-bornyl (E)-3,4,5-trimethoxycinnamate were revised and assigned completely.

(3S)-1,2,3,4-Tetrahydro-ß-carboline-3-carboxylic acid from Cichorium endivia. L induces apoptosis of human colorectal cancer HCT-8 cells.

Cichorium endivia. L, consumed either cooked or eaten raw in salads, is a popular kind of vegetable cultivated all around the World. Its components have been widely used in folk medicine in anti-inflammatory therapy. However, the anti-cancer activity of the components has never been reported. In this study, (3S)-1,2,3,4-tetrahydro-ß-carboline-3-carboxylic acid (1), an amino acid isolated from C. endivia. L, was found for the first time to show cytotoxic activity in colorectal cancer cell line HCT-8. Compound 1 at concentrations of 0.5-4 µM induced apoptosis of HCT-8 cells in a dose-dependent manner. The compound 1-induced apoptosis in HCT-8 cells was accompanied by the loss of mitochondrial membrane potential, the activation of caspase-3, caspase-8 and caspase-9, the up-regulation of Bax and the down-regulation of Bcl-2. In addition, compound 1 suppressed the activation of NF-κB, which acts as an inhibitor of apoptosis. Taken together, these results suggested that compound 1 could significantly induce apoptosis of HCT-8 cells through the suppression of NF-κB signaling pathway, and thus can be considered as a potential candidate for developing chemotherapeutic drugs against cancer.

Hepatoprotective activity of Cichorium endivia L. extract and its chemical constituents.

The objective of the present study was to investigate the in vitro and in vivo hepatoprotective properties of Cichorium endivia L. extract (CEE), and to identify its chemical constituents. CEE significantly blocked the oxidative stress and cytotoxicity induced by tert-butyl hydroperoxide (t-BHP) in HepG2 cells. Meanwhile, oral administration of CEE to mice before the treatment of t-BHP exhibited a markedly protective effect by lowering serum levels of ALT and AST, inhibiting the changes in liver biochemistry including MDA, SOD, GSH and GST, as well as ameliorating the liver injuries according to the histopathological observations. According to the acute oral toxicity test, the LD(50) of CEE was greater than 5,000 mg/kg, which demonstrates that the CEE can be considered practically non-toxic. Phytochemical analysis of CEE showed the presence of five compounds identified as 2-furanmethanol-(5'→11)-1,3-cyclopentadiene-[5,4-c]-1H-cinnoline, which is a new cinnoline derivative derived from a natural source but not synthesis, 2-phenylethyl-ß-D-glucopyranoside, kaempferol-3-O-ß-D-glucoside, kaempferol, and adenosine. In the ORAC assay, CEE and its constituents kaempferol and kaempferol-3-O-ß-D-glucoside had considerable antioxidant potency. Taken together, CEE protects hepatic tissue from oxidative damage in vitro and in vivo, potentially due to its phenolic substances, and does not cause acute oral toxicity, which suggests that CEE may be a valid and safe remedy to cure liver disease.

Two novel biphenyl dimers from the heartwood of Caesalpinia sappan.

Two novel biphenyl dimers, caesappanin A (1) and B (2), were isolated from the ethanol extract of the heartwood of Caesalpinia sappan. Their structures were elucidated on the basis of spectroscopic data including IR, HRESIMS, 1D and 2D NMR. Preliminary bioassays showed that compound 1 possessed potent cytotoxic effects against 4 cell lines including HCT-8, BGC-823, A549 and A2780 with IC(50) between 1.67µM and 4.88µM.

Fingerprinting analysis of Rhizoma chuanxiong of commercial types using 1H nuclear magnetic resonance spectroscopy and high performance liquid chromatography method.

The (1)H nuclear magnetic resonance ((1)H NMR) fingerprints of fractionated non-polar extracts (control substance for a plant drug (CSPD) A) from Rhizoma chuanxiong, the rhizomes of Ligusticum chuanxiong Hort., of seven specimens from different sources were measured on Fourier Transform (FT)-NMR spectrometer and assigned by comparing them with the (1)H NMR spectra of the isolated pure compounds. The (1)H NMR fingerprints showed exclusively characteristic resonance signals of the major special constituents of the plant. Although the differences in the relative intensity of the (1)H NMR signals due to a discrepancy in the ratio of the major constituents among these samples could be confirmed by high performance liquid chromatography analysis, the general features of the (1)H NMR fingerprint established for an authentic sample of the rhizomes of L. chuanxiong exhibited exclusive data from those special compounds and can be used for authenticating L. Chuanxiong species.

Chemical constituents of the stems of Ephedra sinica.

A new naphthalene derivative, 1-methyl-2,3-methylenedioxy-6-naphthalenecarboxylic acid methyl ester (1), and a new alkaloid, ( +/- )-1-phenyl-2-imido-1-propanol (2), together with the four known compounds, ephedrine, pseudoephedrine, N-methylephedrine, and 6-methoxykynurenic acid, have been isolated from the stems of Ephedra sinica, a famous traditional Chinese herbal medicine. The structures of 1 and 2 were determined by spectroscopic methods, including 1D- and 2D-NMR experiments as well as HR-EI-MS analysis.