Antibacterial constituents from Stemona sessilifolia

Bioassay-guided fractionation led to the isolation of eight compounds from Stemona sessilifolia. Of the eight isolates, three new bibenzyls, stilbostemins M-O (1-3), and a new tocopherol, 6-methoxy-3,4-dehydro-δ-tocopherol (4) were revealed together with four known compounds 3,5-dihydroxy-2'-methoxy bibenzyl (5), 3,5-dihydroxy bibenzyl (6), β-tocopherol (7), and γ-tocopherol (8). Compounds 5, 6, and 8 exhibited strong antibacterial activities against Staphylococcus aureus and S. epidermidis.     

Triterpenes from Tripterygium wilfordii Hook

Two new friedelane-type triterpenes, tripterfrielanons A (1) and B (2), along with six known triterpenoids, friedelin (3), canophyllal (4), canophyllalic acid (5), 3-oxo-29-hydroxyfriedelane (6), wilforlide A (7), wilforlide B (8), have been isolated from the EtOH extract of the roots of Tripterygium wilfordii Hook.f. Compounds 4, 5, 6 were isolated for the first time from this plant. The new triterpenes 1 and 2 exhibited mild cytotoxic activity against human Hela cell lines in vitro. The assay showed the IC₅₀ of 1 and 2 were 8.5 and 25 μg/mL, respectively.     

Absolute configuration determination of angular dihydrocoumarins from Peucedanum praeruptorum

From Peucedanum praeruptorum, one new khellactone ester (3'R)-O-acetyl-(4'S)-O-angeloylkhellactone (3), as well as four known angular dihydropyranocoumarins (1, 2, 4, 5) have been isolated. On the basis of NMR spectra and X-ray crystallography, their structures were determined. We have elucidated their absolute configuration by either chiral separation of their alkaline hydrolysis products with Rp-18 HPLC eluted with 5% hydroxypropyl-β-cyclodextrin (β-HCD) or by measurement of their CD spectra. A general rule relating the position and absolute stereochemistry of the khellactone esters to the sign of their Cotton effects in CD curves is proposed.     

Two new diterpenoid dimers,fritillebinide D and E,from bulbs of Fritillaria ebeiensis

Two new ent-kaurane diterpenoid dimers, fritillebinide D (1) and fritillebinide E (2), were isolated from bulbs of Fritillaria ebeiensis G.D. Yu et G.Q. Ji. Their structures have been determined to be ent-3β-acetoxy-kauran-16β, 17-acetal ent-3β-acetoxy-16β-kauran-17(R)-aldehyde (1) and ent-3β-acetoxy-kauran-16β,17-acetal ent-3β-acetoxy-16β-kauran-17(S)-aldehyde (2) by means of spectral analysis.     

Oleanane-type triterpenes from Ludwigia octovalvis

Two new oleanane-type triterpenes, (23Z)-feruloylhederagenin (1) and (23E)-feruloylhederagenin (2), together with two known oleanane-type triterpenes, β-amyrin acetate and β-amyrin palmitate, have been isolated from the whole plant of Ludwigia octovalvis. The structures of 1 and 2 were characterised on the basis of spectral evidence.     

Triterpenoids from the stems of Myricaria paniculata

Two new pentacyclic triterpenoids myricarin A and B (1 and 2) have been isolated from the stems of Myricaria paniculata, together with seven known compounds, myriconal, 28-hydroxy-14-taraxeren-3-one, epi-friedelanol, β-sitosterol, 4-methyl stigmast-7-en-3-ol, 12-hentriacontanol and 1-triacontanol. Their structures have been established by chemical and spectroscopic methods. Cytotoxic activities of 1 and 2 have been evaluated against several different cell lines.     

Structural elucidation of fritillahupehin from bulbs of Fritillaria hupehensis Hsiao et K.C. Hsia

A novel diterpenoid ester, fritillahupehin (1) and three known fatty acids, palmitic acid (2), lignoceric acid (3) and azelaric acid (4), have been isolated from the bulbs of Fritillaria hupehensis Hsiao et K.C. Hsia. The structure of fritillahupehin has been established to be ent-kauran-16β-yl lignocerate by means of spectroscopic and chemical evidence. Compounds 2-4 were isolated from Fritillaria sp. for the first time.     

A New Bicoumarin from Stellera Chamaejasme L

Thirteen compounds were isolated from roots of Stellera chamaejasme L. (Thymelaeaceae). They are β-sitosterol (2), simplexin (3), pimelea factor P2 (4), daucosterol (5), (+)-3-hydroxy-1,5-diphenyl-1-pentanone (6), 4-ethoxy-benzoic acid (7), 2,4,6-Trimethoxy-benzoic acid (8), (+)-afzelechin (9), fumaric acid (10), N,N-dimethyl-L-aspartic acid (11), umbelliferone (12), daphniretin (13) and a novel bicoumarin named bicoumastechamin (1). Among the known compounds, 7, 8, 9, 10 and 11 were first isolated from this plant, and 6 was first isolated from the natural resources. Their structures have been elucidated on the basis of spectral data. In vitro bioassays showed that 4 inhibited cancer cell growth, 13 exhibited immunomodulatory activity, and 6 exhibited both immunomodulatory and anti-tumor activity.     

Two new and four known polyphenolics obtained as new cell-cycle inhibitors from Rubus aleaefolius Poir

Two new polyphenolics, rubuphenol (1) and sanguiin H-2 ethyl ester (2), were isolated together with ellagic acid (3), ethyl gallate (4), 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose (5) and 1,2,3,6-tetra-O-galloyl-β-D-glucopyranose (6) as new cell-cycle inhibitors from Rubus aleaefolius by bioassay-guided separation procedure and the structures of 1 and 2 were elucidated by spectroscopic method. Compounds 1 - 6 inhibited the cell cycle progression of tsFT210 cells at the G₀/G₁ phase with the MIC values of 14.6 μM (1), 22.1 μM (2), 10.3 μM (3), 7.8 μM (4), 7.9 μM (5) and 6.6 μM (6).     

Triterpenoid Saponins from Leaves and Stems of Panax Quinquefolium L

In the chemical investigation on the saponin composition of leaves and stems of Panax quinquefolium L., two new minor dammarane saponins, quinquenoside L₁ (1) and L₂ (2) have been isolated. By means of physico-chemical evidences and spectral analysis their structures were established as 3-O-[β-D-glucopyranosyl-(1-2)-β-D-glucopyranosyl]-20-O-β-D-glucopyranosy-dammara-23,25-diene-3β, 12β, 20(S)-triol (1) and 3-O-[β-D-glucopyranosyl-(1-2)-β-D-glucopyranosyl]-20-O-β-D-D-glucopyranosyl-(24Z)-dammar-24-ene-3β, 12β, 20(S), 26-tetraol (2).     

Triterpenoid saponins from Vaccaria segetalis

A new triterpenoid saponin, named segetoside C (1), and two known saponins, vaccaroid A (vaccaroside A) (2) and dianoside G (3), have been isolated from the seeds of Vaccaria segetalis. On the basis of chemical reaction and spectral data, the structure of segetoside C (1) has been established as: gypsogenic acid-28-O-[β-D-glucopyranosyl-(1 → 3)]-[6-O-acetyl-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranoside.     

Chemical Constituents from the Leaves of Magnolia Denudata

20 compounds were isolated from the leaves of Magnolia denudata including 16 lignans, which belong to 6 structural types. Except for (7R, 8S, 1'S) -δ^8' - 1', 4' - dihydro - 5'- methoxy - 3, 4 -methylenedioxy - 4' - oxo -7.O.2', 8.1' - neolignan (6), magliflonenone (9), 2,5' - diene-2', 8'- epoxy - 5' - methoxy - 8 - methyl - 4' - oxo - 3,4-methylenedioxy - spiro (5,5) - undecane (10), veraguensin (16) and β-sitosterol (20), the other 15 compounds were obtained from this species for the first time. The absolute configurations of 3 compounds (1,4,10) were determined by CD spectroscopy for the first time. The anti-inflammatory activities of compounds 1, 2 and 16 were assessed and 2 was shown to have significant inhibition effect on mice hind-paw edema induced by carrageenan.     

ent-Kaurenoids from the roots of Cacalia pilgeriana

Two new ent-kaurenoids,19-acetoxyl-ent-3β,17-dihydroxykaur-15-ene (1), 19-acetoxyl-ent-3β-hydroxykaur-15-en-17-al (2), together with seven known ent-kaurenoids: ent-kaur-16-en-19-al (3), ent-kaur-16-en-19-oic acid (4), ent-kauran-16β,17-diol (5), ent-15β, 16β-epoxy-17-hydroxykauran-19-oic acid (6),19-acetyl-ent-3β-hydroxyl-kaur-16-ene (7), ent-3β,19-dihydroxykaur-16-ene (8), ent-17-hydroxykaur-15-ene (9), were isolated from Cacalia pilgeriana. Their structures were elucidated by spectroscopic methods including 2D NMR spectral analysis.     

Chemical constituents of Pseudopterogorgia species of the Indian ocean

A new ceramide, (2S,3R,4E)-1,3-dihydroxy-2-[(hexadecanoyl)amino]-nonadeca-4-ene (1), cholest-5-en-3β,7β,19-triol (2), identified as its, peracetyl derivative (3), and batyl alcohol (4) were isolated from Pseudopterogorgia species. 1 exhibited antibacterial activity against Gram-positive and Gram-negative bacteria.     

Ether-soluble resin glycosides from the roots of Ipomoea batatas

Two new resin glycosides, batataosides I (1) and II (2), and five known compounds, friedelin (3), scopoletin (4), octadecyl caffeate (5), β-sistosterol (6) and daucosterol (7), were isolated from the roots of Ipomoea batatas. Their structures have been determined based on the chemical and spectral data. Batataosides I and II have novel structures because the core simonic acid B was esterised with cinnamic acid for the first time, and three different substituent esterification groups in one resin glycoside is scarce. The absolute configuration of the aglycone was elucidated to be S by Mosher's method.     

Structural elucidations of two ent-kaurane dimers from bulbs of Fritillaria ebeiensis var. purpurea

A novel ent-kaurane diterpenoid dimer, fritillebinide B (1) together with one known diterpenoid dimer fritillebinide A (2) were isolated from the bulbs of Fritillaria ebeiensis var. purpurea G.D. Yu et P. Li. Compound 1 has been established to be ent-3β-acetoxy-kauran-16β,17-acetal ent-16β-kauran-17(R)-aldehyde (1) by means of spectral analysis and chemical evidence.     

Bioactive coumarins from Boenninghausenia sessilicarpa

Bioassay guided fractionation of Boenninghausenia sessilicarpa (Rutaceae) resulted in the isolation of a new dimeric coumarin glucoside 9'-methoxyl rutarensin (1) and a cytotoxic compound rutamarin (4), as well as an antivirus component leptodactylone (8), together with six known coumarins. Their structures were elucidated by 1D- and 2D NMR spectroscopy and ESI-MS analyses, respectively. Rutamarin (4) showed significant inhibitory activities against A-549, Bel-7402, HepG-2 and HCT-8 tumour cell lines with IC₅₀s of 1.318, 2.082, 2.306 and 2.497 μg/ml. In addition, leptodactylone (8) showed potent protective activity on cells infected by SARS-CoV with ratio of 60% at 100 μg/ml.     

Three new isoprenylated flavonoids from the roots of Sophora flavescens

Three new flavonoids isoprenylated as 2,2-dimethyl-dihydropyran groups, named sophoranodichromanes A-C (1-3), have been isolated from the roots of Sophora flavescens, together with the known compounds, chrysophanol (4), soyasapogenol B (5) and β-sitosterol (6). Their structures have been elucidated by spectroscopic methods.     

Carbazole alkaloids as new cell cycle inhibitor and apoptosis inducers from Clausena dunniana Levl

Carbazole alkaloids, 3-methylcarbazole (1), murrayafoline A (2), girinimbine (3), mahanimbine (4) and bicyclomahanimbine (5), were isolated for the first time from Clausena dunniana Levl. by bioassay-guided separation procedure and were identified by spectroscopic methods. Compounds 1 - 5 showed growth inhibitory activity (1, IC₅₀ 25 μg/ml) on human fibrosarcoma HT-1080 cells and cell cycle M-phase inhibitory (2, MIC 0.78 μg/ml) and apoptosis inducing (2, MIC 1.56 μg/ml; 3, MIC 25 μg/ml; 4, MIC 20 μg/ml; 5, MIC 30 μg/ml) activities on mouse tsFT210 cells, respectively, and 2 - 5 provided the first examples of carbazole alkaloids as new cell cycle inhibitors and apoptosis inducers.     

Cytotoxic ent-kauranoids from Isodon leucophyllus

Two new compounds, baiyecrystals D and E (1, 2), together with eight known analogues, xerophilusin B (4), macrocalin B (5), oridonin (6), rosthorin A (7), lasiocarpanin (8), rabdoternin A (9) and phyllostachysin A (10) and B (11), were isolated from the aerial parts of Isodon leucophyllus. The structures of 1 and 2 and 4-11 were elucidated on the basis of spectroscopic methods, especially the 2D NMR spectral analysis. Compounds 2, 6-8 and 10 were evaluated for their antineoplastic activities in vitro. Among them, lasiocarpanin (8) showed significant inhibitory activities against K562 and Bcap37 cells, with the IC₅₀ values of 0.13 and 1.26 μg mL_-1, respectively, which were lower than those of the positive control.