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).     

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.     

Triterpene saponins from Lysimachia christinae

Seven triterpene saponins were isolated from Lysimachia christinae and identified as lysichriside A (1), lysichriside B (2), primulanin (3), lysikokianoside 1 (4), anagallisin C (5), ardisiacrispin A (6), and ardisicrenoside B (7). Compounds 1 and 2 are new triterpene saponins, compounds 3, 5, and 7 were isolated from this genus, and compounds 4 and 6 were isolated from this species for the first time. Their structures were elucidated by means of 1D and 2D NMR experiments.     

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.     

Studies on the alkaloid constituents of Evodia rutaecarpa (Juss) Benth var. bodinaieri (Dode) Huang and their acute toxicity in mice

Six alkaloids (1-6) have been isolated from the fruits of Evodia rutaecarpa (Juss) Benth var. bodinaieri (Dode) Huang, two of which are new compounds, identified as 2-undecyl-4(1H)-quinolone (4) and 1-methyl-2-undecanone-10'-4(1H)-quinolone (5); the known compounds were identified as rutaecarpine (1), evodiamine (2), 1-methyl-2-undecyl-4(1H)-quinoline (3) and 2-undecanone-10'-4(1H)-quinolone (6). Compounds 1-5 were evaluated for their acute toxicity.     

Five new norditerpenoid alkaloids from Aconitum sinomontanum

From the roots of Aconitum sinomontanum, five new norditerpenoid alkaloids, sinomontanitines A (1) and B (2), sinomontanines A (3), B (4) and C (5), were isolated together with the known alkaloids lappaconitine (6) and ranaconitine (7), The structures of the new alkaloids were determined by spectral analysis.     

Anthraquinones from Gladiolus gandavensis

Five new anthraquinones have been obtained from the ethanolic extracts of the subterranean corms of Gladiolus gandavensis Van Houtt. Their structures were elucidated as 3,8-dihydroxy-6-methoxy-1-methyl-anthraquinone (gandavensin D, 1), methyl 3,8-dihydroxy-6,7-methylenedioxy-1-methyl-anthraquinone- 2-carboxylate (gandavensin E, 2), 2,3,8-trihydroxy-6-methoxy-1-methoxymethyl-anthraquinone (gandavensin F, 3), 8-hydroxy-3,6-dimethoxy-1-methyl-anthraquinone-2-carboxylic acid (gandavensin G, 4) and 1,7-dihydroxy-3,6-dimethoxy-anthraquinone (gandavensin H, 5) on the basis of spectral data. The known compounds isolated for the first time from this plant have been determined to be methyl 3,6,8-trihydroxy-7-methoxy-1-methyl-anthraquinone-2-carboxylate (6), methyl 3,6,8-trihydroxy-1-methyl-anthraquinone-2-carboxylate (7), 3,8-dihydroxy-6-methoxy-1-methyl-anthraquinone-2-carboxylic acid (8), 3,6,8-trihydroxy-1-methyl-anthraquinone-2-carboxylic acid (9), 6,8-dihydroxy-3-methoxy-1-methyl-anthraquinone-2-carboxylic acid (10), methyl 3,8-dihydroxy-6-methoxy-1-methyl-anthraquinone-2-carboxylate (11) and methyl 3,7,8-trihydroxy-1-methyl-anthraquinone-2-carboxylate (12).     

Heteroclitin H, a new lignan from Kadsura heteroclita

A new dibenzocyclooctadiene lignan, heteroclitin H (1), was isolated together with seven known compounds, heteroclitin D (2), interiorin B (3), interiorin (4), neokasuranin (5), interiotherin C (6), gomisin J (7) and (+)-anwulignan (8), from the stems of Kadsura heteroclita. Their structures were elucidated by spectroscopic methods. This is the first report of the isolation of compounds 3, 5, 6, 7 and 8 from K. heteroclita.     

Stilbene derivatives from Gnetum cleistostachyum

Three new stilbene derivatives, named gnetucleistol A (1), B (2) and C (3), together with four known compounds, gnetifolin A (4), p-hydroxycinnamic acid (5), piceatannol (6) and resveratrol (7), were isolated from Gnetum cleistostachyum C.Y. Cheng (Gnetaceae). Their structures were elucidated on the basis of spectroscopic evidence (EI-MS, UV, IR, NOE, ¹H, ¹³C and 2D NMR).     

Three new triterpenoid saponins from the rhizomes of Impatiens pritzellii var. hupehensis

Three new triterpenoid saponins, impatiprins A-C (1-3), together with a known triterpenoid (4) and two known triterpenoid saponins (5, 6), were isolated from the rhizomes of Impatiens pritzellii Hook. f. var. hupehensis Hook. f. The structures of 1-3 were determined by 1D and 2D NMR, FAB-MS techniques and chemical methods. Compounds 1 and 2 showed weak cytotoxicities against S-180, HeLa and HepG2 cell lines.     

Stilbenoids from Stemona japonica

Three new dihydrostilbenes, stilbostemins J-L (1-3), and a new dihydrophenanthrene, stemanthrene F (4), were isolated from the roots of Stemona japonica together with two known bibenzyls, 3,5-dihydroxy-4-methylbibenzyl (5) and 3,5-dihydroxy-2'-methoxy-4-methylbibenzyl (6). Their structures were elucidated by spectroscopic analyses. Compounds 3-6 exhibited strong antibacterial activities against Staphylococcus aureus and Staphylococcus epidermidis.     

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.     

Studies on chemical constituents from Ilex pubescens

Two new phenolic glycosides, ilexpubsides A and B, along with four known lignan glycosides were isolated from the roots of Ilex pubescens. By spectral evidence, the structures of the new compounds were elucidated as 4-O-β-D-[6'-O-(4'-O-β-D-glucopyranosylvanilloyl)glucopyranosyl] vanillic acid (1) and syringinic 6'-O-β-D-xylopyranoside (2). The known compounds were identified to be liriodendrin (3), (-)-olivil (4), tortoside A (5) and (+)-cyclo-olivil (6). All compounds were first isolated from Ilex pubescens.     

Further flavonol and iridoid glycosides from Ajuga remota aerial parts

Five new iridoid glycosides characterised as 6-keto-8-acetylharpagide (1), 6,7-dehydro-8-acetylharpagide (2), 7,8-dehydroharpagide (3), 8-acetylharpagide-6-O-β-glucoside (4), harpagide-6-O-β-glucoside (5) together with three flavonol glycosides, myricetin 3-O-rutinoside-4'-O-rutinoside (6), myricetin 3-O-rutinoside-3'-O-rutinoside (7) and isorhamnetin 3-O-rutinoside-7-O-rutinoside-4'-O-β-glucoside (8) have been isolated from the aerial parts of Ajuga remota. Also isolated were two known compounds ajugarin IV and ajugarin V. Their structures were established using spectroscopic methods including UV, IR, FAB-MS, HR-MS, 1D and 2D NMR techniques.     

9, 10-Dihydrophenanthrene derivatives from Pholidota yunnanensis and scavenging activity on DPPH free radical

Three new 9,10-dihydrophenanthrene derivatives named phoyunnanins A-C, together with six known 9,10-dihydrophenanthrene constituents, 4,4',7,7'-tetrahydroxy-2,2'-dimethoxy-9,9',10,10'-tetrahydro-1,1'-biphenanthrene (4), lusianthridin (5), eulophiol (6), 2,4,7-trihydroxy-9,10-dihydrophenanthrene (7) and imbricatin (8), were isolated from the 60% ethanolic extract of air-dried whole plant of Pholidota yunnanensis Rolfe. The structures of phoyunnanins A-C were established as 6-[2'-(3',3'-dihydroxy-5'-methoxybibenzy)]-4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (1), 6-[6'-(trans-3',3'-dihydroxy-5'-methoxystilbeny)]-4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (2) and 4,4',7,7'-tetrahydroxy-2,2'-dimethoxy-9,9',10,10'-tetrahydro-1,6'-biphenanthrene (3), respectively, on the basis of the spectroscopic analysis. All eight compounds (1-8) were found to show the DPPH free radical scavenging activity with EC₅₀ from 8.8 to 55.9 μM.     

Three new norlignans from Curculigo capitulata

From the ethanolic extract of the rhizomes of Curculigo capitulata have been isolated, and structurally elucidated by spectral evidences and chemical methods, three new norlignans, capituloside (1), a mixture of curculigenin (2) and isocurculigenin (3), along with four known compounds (4-7), a mixture of 1-O-methylcurculigine (4) and 1-O-methylisocurculigine (5) and a mixture of curculigine (6) and isocurculigine (7).     

New anthraquinones from Gladiolus gandavensis

Two new anthraquinones, methyl 8-hydroxy-3-methoxy-6,7-methylenedioxy-1-methylanthraquinone-2-carboxylate (gandavensin A, 1) and methyl 8-hydroxy-3,6,7-trimethoxy-1-methylanthraquinone-2-carboxylate (gandavensin B, 2), have been isolated from the light petroleum extract of the subterranean corm of Gladiolus gandavensis Van Houtt., along with methyl 8-hydroxy-3,6-dimethoxy-1-methylanthraquinone-2-carboxylate (3), methyl trans-p-methoxycinnamate (4), 5,7-dimethoxy-2-methylchromone (5), and 5-hydroxy-2-hydroxymethyl-7-methoxychromone (6). Their structures were elucidated on the basis of spectral data.     

Terpenoids and sterols from Lagerstroemia speciosa

The leaves of Lagerstroemia speciosa afforded a new natural product, 31-norlargerenol acetate (4), along with known compounds 24-methylenecycloartanol acetate (1), its 31-nor analog (2), largerenol acetate (3), tinotufolins C (5) and D (6), lutein, phytol, sitosterol and sitosterol acetate. The structure of 4 was elucidated by 1D and 2D NMR and mass spectroscopy.     

Furostanoside from Asparagus filicinus

A new furostanoside, named aspafilioside D (1), together with the five known compounds officinalisnin-II (2), Asp-IV' (3), (+)-4'-O-methyl-nyasol (4), (+)-nyasol (5) and tormentic acid (6), have been isolated from the roots of Asparagus filicinus. The structure of 1 has been elucidated on the basis of spectral data.     

Coumarins from Coriaria nepalensis

Two new coumarins (1) and (2), along with seven known coumarins 3-9, were isolated from the leaves and stems of Coriaria nepalensis Wall. The two new compounds were established as 7-hydroxy-6-methoxy-3,8-bis(3-methyl-2-butenyl) coumarin (1) and 7-hydroxy-6-methoxy-3-(3-methyl-2-butenyl) coumarin (2), on the basis of 1D and 2D NMR techniques. The known compounds 3, 6-9 were isolated from this plant for the first time.