New constituents from Crinum latifolium with inhibitory effects against tube-like formation of human umbilical venous endothelial cells

Six compounds (1-6) were isolated from the methanol extract of Crinum latifolium by bioassay-guided separation. Among the six isolates, compounds 2 and 6 were new metabolites. Their structures were established as 4-senecioyloxymethyl-3,4-dimethoxycoumarin (2) and 5,6,3'-trihydroxy-7,8,4'-trimethoxyflavone (6) based on spectroscopic analyses. Compound 2 was found to be strongly inhibitory against the in vitro tube-like formation of human umbilical venous endothelial cells (HUVECs) while manifesting no cytotoxicity in tumor cell lines (B16F10, HCT116). Significant inhibitory activity (inhibition percentage, 53.5%) was still observed at concentrations as low as 1 microg/mL. Compound 6 showed a modest inhibitory effect on the tube-like formation of HUVECs. Other compounds, including cycloartenol (1), 4',7-dihydroxy-3'-methoxyflavan (3), 4',7-dihydroxyflavan (4), and 2',4',7-trihydroxydihydrochalcone (5) were found to be nearly inactive.     

Antiangiogenic polyketides from Peperomia dindygulensis Miq

Two new polyketides: 2Z-(heptadec-12-enyl)-4-hydroxy-3,4,7,8-tetrahydro-2H-chromen-5(6H)-one (1) and 2-(heptadec-12-enyl)-5-hydroxy-5,6,7,8-tetrahydrochromen- 4-one (2), together with eleven known compounds: 4-hydroxy-2-[(3,4-methylenedioxy- phenyl)tridecanoyl] cyclohexane-1,3-dione (3), oleiferinone (4), 4-hydroxy-2-[(3,4- methylenedioxyphenyl)undecanoyl]cyclohexane-1,3-dione (5), 4-hydroxy-2-[(11-phenyl- undecanoyl)cyclohexane-1,3-dione (6), proctorione C (7), surinone C (8), 5-hydroxy- 7,8,4'-trimethoxyflavone (9), 5-hydroxy-7,8,3',4'-tetramethoxyflavone (10), 5-hydroxy- 7,3',4'-trimethoxyflavone (11), 5,8-dihydroxy-7,3',4'-trimethoxyflavone (12) and cepharanone B (13) were isolated from the whole plant of Peperomia dindygulensis Miq. Their structures were elucidated by spectroscopic methods, including 2D-NMR techniques. Compounds 2, 3, 5 and 8 inhibited human umbilical vein endothelial cell (HUVEC) proliferation and compounds 5 and 8 sharply suppressed HUVEC tube formation.     

Spicachlorantins G-J, new lindenane sesquiterpenoid dimers from the roots of Chloranthus spicatus

Four new lindenane sesquiterpenoid dimers, spicachlorantins G-J (1-4), were isolated from the roots of Chloranthus spicatus together with seven known compounds, including chloramultilide A, shizukaol B, shizukaol D, shizukaol F, shizukaol P, chlorahololide D, and cycloshizukaol A. The planar structures of the new compounds were established by 1D-, 2D-NMR, and MS analyses. The absolute configurations of these compounds were determined by analyzing rotating Overhauser enhancement and exchange spectroscopy (ROESY) and circular dichroism (CD) spectra.     

Bioactive compounds from Selaginella involven Spring that protect PC-12 cells

Two new compounds named as 3b 12 16-trihydroxy-6 8 11 13-abietatrien（1） （8R 80S）-4 40 8-trihydroxyl-3 30-dimethoxyl-90-lignanolide（2） and a new natural product 4 40-dihydroxyl-3 30 5 50-dimethoxyldiphenyl diketone（3） were isolated from the whole herbs of Selaginella involven Spring.The structures were elucidated by spectroscopic analyses including UV,IR,1D,2D NMR and MS methods.Additionally,these three compounds exhibited potent protective effect against the injury of PC-12 cells induced by hypoxia/reoxygenation.     

Iridoids from Neopicrorhiza scrophulariiflora and their hepatoprotective activities in vitro

Four new non-glycosidic iridoids, piscrocins D (1), E (2), F (6), and G (7), as well as two new iridoid glycosides, piscrosides A (8) and B (9), were isolated from the roots of Neopicrorhiza scrophulariiflora (Scrophulariaceae), together with seven known iridoids. The structures of the isolated compounds were established by means of 1D and 2D NMR spectroscopy and chemical methods. The hepatoprotective activities of these compounds were evaluated by measuring their effects on CCl(4)-induced hepatocytes damage in vitro, and the structure-activity relationships were also discussed.     

Two new isoaurones derivatives from Callistephus chinensis flower

Two new isoaurones derivatives were obtained from Callistephus chinensis flower. Their structures were elucidated on the basis of extensive spectroscopic analyses. Both of the new compounds were evaluated cytotoxic activity. Phytochemical investigation of Callistephus chinensis flower led to the isolation of two new isoaurones derivatives (Z)-4′,4,10-trihydroxy-siamaurone (1) and (E)-4′,4,10-trihydroxy-siamaurone (2). The structures of these new compounds were identified by the interpretation of spectroscopic data (mainly 1D and 2D NMR) and by comparison with data reported in the literature. Both of the new compounds were evaluated for their cytotoxicity.     

锦灯笼果实的化学成分研究

从锦灯笼中分离得到5个甾体类化合物,分别鉴定为酸浆素A(1,alkekengilin A)、酸浆素B(2,alkekengilin B)、酸浆苦素D(3,physalin D)、酸浆苦素P(4,physalin P)、4,7-二去氢新酸浆苦素B(5,4,7-didehydro-neophysalin B).其中酸浆素A(1,alkekengilin A)和酸浆素B(2,alkekengilin B)为新的天然产物.运用现代波谱技术对上述化合物的结构进行了确证.     

Tyrolobibenzyls – Novel Secondary Metabolites from Scorzonera humilis

Tyrolobibenzyls A ( 2 ), B ( 3 ), and C ( 4 ) were isolated from Scorzonera humilis (Asteraceae) of Tyrolean origin. Compounds 2 and 3 possess a unique phenylethyl‐benzofuran backbone and represent a new class of natural compounds. Structural assignments are based on 1D and 2D NMR as well as MS data. Furthermore, peracetylated derivatives of compounds 3 and 4 were synthesized. Pharmacological evaluation of these compounds by the [³H]thymidine assay showed no pronounced cytotoxicity.     

Phthalide metabolites produced by mangrove endophytic fungus Pestalotiopsis sp. SAS4

Two new phthalide derivatives ( 1 – 2 ) and four known phthalide compounds ( 3 – 6 ) were purified from the culture of a mangrove endophytic fungus Pestalotiopsis sp. SAS4. Their chemical structures were established by analyses of 1D and 2D nuclear magnetic resonance (NMR) and high resolution mass spectrometry (HR-MS) spectroscopic data. All of these compounds were evaluated in vitro for antibacterial, cytotoxicity, and resistance to hypoxic–ischemic injury activities.     

New Triterpenes from Gymnema sylvestre

Phytochemical investigation of the aerial parts of Gymnema sylvestre has led to the isolation of seven new triterpenes, six oleane types ( 5, 7 – 11 ) and a new lupane type ( 12 ), and of the six known analogues 1 – 4, 6 , and 13 . The structures and relative configurations of these compounds were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR spectroscopy and mass spectrometry, and by the comparison of their NMR data with those of related compounds.     

New triterpenoids isolated from the root bark of Ulmus pumila L

Three new triterpenoids, 1-3, were isolated from the dried root bark of Ulmus pumila. Along with the three new compounds, six known triterpenoids, epifriedelanol (4), friedelin (5), oleanolic acid (6), maslinic acid (7), camaldulenic acid (8), and arjunolic acid (9) were also isolated. The structures of new compounds were established as ulmudiol (bauer-7-ene-1alpha,3beta-diol, 1), dehydroulmudiol [bauer-7,9(11)-diene-1alpha,3beta-diol, 2], and ulmuestone [3alpha-hydroxy-11alpha-(4'-hydroxy-3'-methoxy)benzoyloxybauer-1-one, 3], on the basis of extensive 1D and 2D NMR spectroscopic data interpretation. In addition, the cytotoxic activities of these compounds are also reported.     

NMR spectroscopic analysis of new spiro-piperidylrifamycins

New spiro-piperidylrifamycin derivatives are presented. These compounds were synthesized from the reaction of 3-amino-4-iminorifamycin S and enantiomerically pure 4-piperidones, which generate diasteroisomeric rifabutin analogues with a new stereocentre at the spiranic carbon. The (1)H and (13)C NMR spectra of these new compounds, and also the configuration of the new stereogenic centres, were assigned using 2D NMR spectroscopic techniques. A preliminary study of the (1)H and (13)C NMR spectra of the starting compounds rifamycin S, 3-amino-4-iminorifamycin S and the related rifabutin was also carried out and as a result, their previously published (13)C NMR data were corrected.     

Carboxylic Acids from <Emphasis Type="Italic">Phyllanthus urinaria</Emphasis>

Five compounds, terephthalic acid mono-[2-(4-carboxy-phenoxycarbonyl)-vinyl] ester (1), (E)-3-(5′-hydroperoxy-2,2′-dihydroxy[1,1′-biphenyl]-4-yl)-2-propenoic acid (2), 3,4,5-trihydroxybenzoic acid (3), succinic acid (or butanedioic acid) (4), and 2,3,4,5,6-pentahydroxybenzoic acid (5), were isolated from Phyllanthus urinaria. The structures of these compounds were elucidated by means of spectral techniques including IR, MS, and 1D/2D NMR. 1 and 2 are new compounds.__________Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 14–17, January–February, 2005.     

New 3',8'-linked biflavonoids from Selaginella uncinata displaying protective effect against anoxia

Seven 3',8'-linked bioflavonoids, including one new compound, (2'S)-2', 3'-dihydroamentoflavone-4'-methyl ether and six known compounds: (2S)-2,3- dihydroamentoflavone-4'-methyl ether, (2S,2'S)-2,3,2',3'-tetrahydroamento- flavone-4'-methyl ether, (2S,2'S)-tetrahydroamentoflavone, (2S)-2,3-dihydro- amentoflavone and (2'S)-2',3'-dihydroamentoflavone (6) and amentoflavone, were isolated from the 60% ethanolic extract of Selaginella uncinata (Desv.) Spring. The structures of these compounds were elucidated mainly by analysis of their 1D and 2D NMR spectroscopic data, and their absolute configurations were determined by circular-dichroism (CD) spectroscopy. All the seven compounds showed protective effect against anoxia in the anoxic PC12 cells assay, in which compound 6 displayed particularly potent activity.     

Two new homoisoflavonoids from Caesalpinia pulcherrima

Two new homoisoflavonoids, (E)-7-methoxy-3-(4'-methoxybenzylidene)chroman-4-one (1) and (E)-7-hydroxy-3-(3',4',5'-trimethoxybenzylidene)chroman-4-one (5), along with three known homoisoflavonoids (Z)-7-hydroxy-3-(4'-methoxybenzylidene)chroman-4-one (isobon ducellin) (2), (E)-7-hydroxy-3-(4'-methoxybenzylidene)chroman-4-one (bonducellin) (3) and (E)-7-hydroxy-3-(2',4'-dimethoxybenzylidene)chroman-4-one (4) were isolated from the whole plant of Caesalpinia pulcherrima. The structures of these new compounds were elucidated by electron impact mass spectrometry (EI-MS) and 1D and 2D-NMR spectral studies. Antimicrobial activity of the new compounds was evaluated.     

Explorations of new quaternary phases in the Ln(III)-V(V)(d0)-Se(IV)-O (Ln = Nd, Eu, Gd, Tb) systems

Systematic explorations of new phases in the Ln(III)-V(V)-Se(IV)-O systems by hydrothermal syntheses led to four new quaternary compounds, namely, Nd(2)(V(V)(2)O(4))(SeO(3))(4)·H(2)O (1), Ln(V(V)O(2))(SeO(3))(2) (Ln = Eu 2, Gd 3, Tb 4). The structure of Nd(2)(V(V)(2)O(4))(SeO(3))(4)·H(2)O features a 3D framework composed of the 2D layers of [N d(SeO(3))](+) bridged by the infinite [VO(2)(SeO(3))](-) chains with the lattice water molecules located at the 6-membered ring tunnels formed. The structure of Ln(V(V)O(2))(SeO(3))(2) (Ln = Eu, Gd, Tb) also features a 3D framework composed of 2D layers of [Ln(SeO(3))](+) bridged by the infinite [(VO(2))(SeO(3))](-) double chains. The 1D vanadium oxide selenite chain of 1 differs significantly from those in compounds 2-4 in terms of the coordination modes of the selenite groups and the connectivities between neighbouring VO(6) octahedra. Luminescent and magnetic properties of these compounds were also measured.     

Structure elucidation of new fusarielins from Fusarium sp. and their antimicrobial activity

Three new fusarielins, 3‐epi‐fusarielin H ( 1 ), 3‐O‐methyl‐fusarielin H ( 2 ), and 3‐O‐methyl‐epi‐fusarielin H ( 3 ), were isolated from the fungus Fusarium sp. together with the known analogues, fusarielins F ( 4 ) and G ( 5 ). The structures of these compounds were elucidated by analysis of their ESI‐HRTOFMS, 1D and 2D NMR spectroscopic data. The new compounds exhibited weak antibacterial effect against Staphylococcus aureus.     

Ent-kaurane diterpenoid glycosides from the leaves of Cussonia racemosa, a Malagasy endemic plant

Six new ent-kaurane diterpenoid glycosides, cussoracosides A (3), B (4), C (5), D (6), E (7), and F (8) were isolated from the dried leaves of Cussonia racemosa, along with two known compounds identified as beta-D-glucopyranosyl ent-16beta,17-dihydroxykauran-19-oate (1) and paniculoside IV (2). The structures of these new compounds were deduced on the basis of chemical and spectroscopic evidence.     

Monoterpene constituents from Cistanche tubulosa--chemical structures of kankanosides A-E and kankanol-

Four new iridoid glycosides, kankanosides A (1), B (2), C (3), and D (4), a chlorinated iridoid, kankanol (5), and an acyclic monoterpene glycoside, kankanoside E (6), were isolated from the methanolic extract of dried stems of Cistanche tubulosa (SCHRENK) R. WIGHT (Orobanchaceae) together with 16 known compounds. The structures of these new compounds (1-6) were determined on the basis of the chemical and physicochemical evidence.     

Polyoxygenated Klysimplexane- and Eunicellin-Based Diterpenoids from the Gorgonian Briareum violaceum

Three new polyoxygenated diterpenoids with a rare 4-isopropyl-1,5,8a-trimethylperhydrophenanthrane structure of the klysimplexane skeleton, briarols A‒C (1‒3), and one eunicellin-based diterpenoid, briarol D (4), were isolated from Briareum violaceum, a gorgonian inhabiting Taiwanese waters. The chemical structures of these compounds were determined by employing extensive analyses of NMR and high-resolution electrospray ionization mass spectrometry (HRESIMS) data. Metabolites 1‒3 were found to possess the rarely found skeleton of the diterpenoid klysimplexin T. All isolated compounds showed very weak cytotoxic activity against the growth of three cancer cell lines. A plausible biosynthetic pathway for briarols A‒C from the coexisting eunicellin diterpenoid briarol D (4) was postulated.