Unusual isomeric corniculatolides from mangrove, Aegiceras corniculatum

Four new isomeric macrolides of combretastatin D-2 congeners named isocorniculatolide A (1), 11-O-methylisocorniculatolide A (2), 11-O-methylcorniculatolide A (3), and 12-hydroxy-11-O-methylcorniculatolide A (4), and the known corniculatolide A (5), arjunolic acid, and maslinic acid were isolated from the CHCl(3) extract of the bark of Aegiceras corniculatum. The structures of the new compounds (1-4) were elucidated by a combination of spectroscopic analysis (1-5), chemical modifications, and single-crystal X-ray analysis (1).     

Streptazones A, B(1), B(2), C, and D: new piperidine alkaloids from streptomycetes

Five new piperidine alkaloids (1-5), named streptazones A, B(1), B(2), C, and D, were isolated from Streptomyces strains FORM5 and A1. Their structures were established on the basis of detailed MS and NMR analysis. Streptazone A (1) exhibited significant cytotoxic activity against selected human tumor cell lines.     

Diterpenoids, norditerpenoids, and secosteroids from the Formosan soft coral Cespitularia hypotentaculata

Four new cespitularane diterpenes, cesputularins I-L (1-4), two new norverticillane norditerpenes, cespitularins M and N (5 and 6), two new verticillane diterpenes, cespitularins O and P (7 and 8), a new norditerpene, cespitularin Q (9) (having a novel carbon skeleton), a new xenicane diterpene, cespitolide (10), and two new secosteroids, 3beta,11-dihydroxy-5beta,6beta-epoxy-9,11-secocholestan-9-one (11) and 3beta,11-dihydroxy-5beta,6beta-epoxy-9,11-secogorgostan-9-one (12), were isolated from the methylene chloride solubles of the Formosan soft coral Cespitularia hypotentaculata Roxas. The structures were elucidated by extensive spectroscopic analysis, and their cytotoxicity against selected cancer cells was measured in vitro.     

Quadranosides I-V, new triterpene glucosides from the seeds of Combretum quadrangulare

Five new triterpene glucosides, quadranosides I-V (1-5), have been isolated from a MeOH extract of the seeds of Combretum quadrangulare, together with 13 known compounds. The structures of compounds 1-5 were elucidated on the basis of spectroscopic analysis. Among the new triterpene glucosides, three compounds (1, 2, 5) showed significant hepatoprotective effects against D-galactosamine (D-GalN)/tumor necrosis factor-alpha (TNF-alpha)-induced cell death in primary cultured mouse hepatocytes.     

Bacopaside III,bacopasaponin G,and bacopasides A,B, and C from Bacopa monniera

Two new saponins, 3-O-[6-O-sulfonyl-beta-d-glucopyranosyl-(1-->3)]-alpha-l-arabinopyranosyl pseudojujubogenin (1) and 3-O-[alpha-l-arabinofuranosyl-(1-->2)]-alpha-l-arabinopyranosyl jujubogenin (2), a new matsutaka alcohol derivative, (3R)-1-octan-3-yl-(6-O-sulfonyl)-beta-d-glucopyranoside (3), a new phenylethanoid glycoside, 3,4-dihydroxyphenylethyl alcohol (2-O-feruloyl)-beta-d-glucopyranoside (4), and a new glycoside, phenylethyl alcohol [5-O-p-hydroxybenzoyl-beta-d-apiofuranosyl-(1-->2)]-beta-d-glucopyranoside (5), were isolated from Bacopa monniera. Their structures were established by NMR, MS, and chemical methods.     

Botryolides A-E, decarestrictine analogues from a fungicolous Botryotrichum sp. (NRRL 38180)

Four new decarestrictine analogues (botryolides A-D; 1- 4), a biosynthetically related gamma-lactone (botryolide E; 5), and the known compounds decarestrictine D ( 6) and sterigmatocystin have been isolated from cultures of a fungicolous isolate of Botryotrichum sp. (NRRL 38180). The structures of these compounds were determined by analysis of 2D NMR and ESIMS data. The relative configurations of 1- 5 were established on the basis of NMR data and/or X-ray diffraction analysis, while the absolute configuration of 1 was assigned using the modified Mosher method.     

Chemical constituents of a marine fungus, Arthrinium sacchari

Three new diterpenes, myrocin D (1), libertellenone E (2), and libertellenone F (3), and a new isocoumarin, decarboxyhydroxycitrinone (4), were isolated from the marine fungus Arthrinium sacchari, together with three known compounds (5-7). The structures of 1-4 were elucidated from spectroscopic data (NMR, MS, IR), and the absolute configurations of 1-3 were determined by X-ray diffraction analysis. The antiangiogenic activity of these compounds was evaluated by measuring their antiproliferation effects on human umbilical vein endothelial cells (HUVECs) and human umbilical artery endothelial cells (HUAECs). Compounds 4-7 showed inhibitory activity.     

Decaspirones A-E, bioactive spirodioxynaphthalenes from the freshwater aquatic fungus Decaisnella thyridioides

Decaspirones A-E (1-5), five new compounds related to the palmarumycins, were isolated from cultures of the freshwater aquatic fungal species Decaisnella thyridioides. The known compound palmarumycin CP1 (6) was also obtained. The structures of 1-5 were determined by analysis of NMR and MS data, and their relative configurations were assigned by analysis of 1H NMR J-values and NOESY data. The structure of the lead compound 1 was confirmed by X-ray crystallographic analysis. Compounds 1-5 possess a trans ring fusion not previously reported in members of this structural class. The absolute configuration of 1 was assigned using the modified Mosher method. Compounds 1-5 showed potent antifungal and antibacterial activity.     

Jerantinines A-G, cytotoxic Aspidosperma alkaloids from Tabernaemontana corymbosa

Seven new indole alkaloids of the Aspidosperma type, jerantinines A-G (1-7), were isolated from a leaf extract of the Malayan Tabernaemontana corymbosa. The structures were established using NMR and MS analysis. Five of the alkaloids isolated and two derivatives (1-5, 8, 9) displayed pronounced in vitro cytotoxicity against human KB cells (IC50 < 1 microg/mL).     

Gusanlungionosides A-D, potential tyrosinase inhibitors from Arcangelisia gusanlung

Four new megastigmane glycosides, named gusanlungionosides A-D (1-4), together with 10 known compounds (5-14), were isolated from the stems of Arcangelisia gusanlung. The structures and absolute configurations of 1-4 were elucidated by comprehensive analysis of their NMR and CD data. Compounds 1-4 exhibited strong inhibitory effects not only on the mushroom tyrosinase activity in vitro but also on melanogenesis in cells.     

Alpha-glucosidase inhibitory anthranols, kenganthranols A-C, from the stem bark of Harungana madagascariensis

One new prenylated 1,4-anthraquinone and three new prenylated anthranols, named kengaquinone (1) and kenganthranols A (2), B (3), and C (4), were isolated from a hexane extract of the stem bark of Harungana madagascariensis. Six known compounds including anthraquinones, anthrones, and xanthones were also isolated and identified. The structures of the new compounds were determined by analysis of spectroscopic data and comparison with data of previously known analogues. Some isolated compounds (3-5, 7-11) were evaluated for their alpha-glucosidase inhibition activity. Compounds 3, 4, 8, and 11 showed significant activity, whereas compounds 7, 9, and 10 were inactive in this test.     

Chaetocochins A-C, epipolythiodioxopiperazines from Chaetomium cochliodes

Three new epipolythiodioxopiperazines, chaetocochins A (1), B (2), and C (3), along with dethio-tetra (methylthio) chetomin (4) and chetomin (5), were isolated from the ethyl acetate extract of the solid-state fermented rice culture of the fungus Chaetomium cochliodes. Their structures were elucidated on the basis of spectroscopic analysis. Compounds 1, 3, and 4 exhibited significant cytotoxicity in vitro against cancer cell lines Bre-04, Lu-04, and N-04.     

Phenolic constituents of the roots of Sophora flavescens

From the roots of Sophora flavescens collected in Taiwan, four new prenylflavonoids, sophoraflavanone K (1), sophoraflavanone L (2), 8-lavandulylkaempferol (3), and cyclokuraridin (4), a new arylbenzofuran, 2-(2,4-dihydroxy-5-prenylphenyl)-5,6-methylenedioxybenzofuran (5), and a new prenyldibenzoyl derivative, sophoradione (6), were isolated. The structures of 1-6 were determined by spectroscopic data analysis. Compounds 2-6 were evaluated for cytotoxic activity against the KB epidermoid carcinoma cell line.     

Cinnafragrins A-C, dimeric and trimeric drimane sesquiterpenoids from Cinnamosma fragrans, and structure revision of capsicodendrin

Two new dimeric sesquiterpenoids and a new trimeric drimane sesquiterpenoid named cinnafragrins A-C (1-3), together with cinnamodial (4), D-mannitol, capsicodendrin (5), and a vitamin E analogue, delta-tocotrienol, were isolated from Cinnamosma fragrans, a Malagasy medicinal plant. The structures of the new compounds were determined on the basis of physical, chemical, and spectroscopic evidence. Capsicodendrin, previously isolated from Capsicodendron dinisii and tentatively suggested to be a tetramer of cinnamodial, was revised structurally as a mixture of C-12'-epimers of 12'-hydroxycinnafragrin B by extensive 2D NMR analysis and X-ray crystallography of the lactone derivative, cinnafragrolide (6). The chemosystematics of the family Canellaceae are discussed.     

The berkeleyamides, amides from the acid lake fungus Penicillum rubrum

We previously reported several novel bioactive hybrid polyketide-terpenoid metabolites from a deep water Penicillium rubrum isolated from Berkeley Pit Lake, Butte, Montana. In this paper we report the structures of four new amides, berkeleyamides A-D (1, 4, 5, 7), isolated from extracts of this fungus. The structures of these compounds were deduced by analysis of NMR data, chemical derivatization, and comparison of their spectroscopic data to those of known compounds.     

Sapinmusaponins F-J, bioactive tirucallane-type saponins from the galls of Sapindus mukorossi

Five new tirucallane-type saponins, sapinmusaponins F-J (1-5), were isolated from the galls of Sapindus mukorossi. The structures of these saponins were elucidated on the basis of spectroscopic analysis including 1D and 2D NMR techniques ((1)H-(1)H COSY, HMQC, HMBC, TOCSY, and NOESY). Compounds 1-5 showed anti-platelet-aggregation effects, but no obvious cytotoxic activity for platelets as assayed by lactate dehydrogenase (LDH) leakage. Compounds 1-5 also showed moderate activity in a 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced Epstein-Barr virus early antigen (EBV-EA) activation assay.     

Trigonosins A-F, daphnane diterpenoids from Trigonostemon thyrsoideum

Phytochemical study of the roots of Trigonostemon thyrsoideum led to the isolation of four new oxygenated daphnane-type diterpenoids, trigonosins A-D (1-4), and two new modified daphnanes, trigonosins E and F (5 and 6). The structures and relative configurations were elucidated on the basis of extensive spectroscopic analysis, including 1D and 2D NMR experiments. All compounds isolated were evaluated for their cytotoxicity against HL-60, A549, and MCF-7 human cancer cell lines.     

Briaexcavatolides K-N, new briarane diterpenes from the gorgonian Briareum excavatum

Four new briarane diterpenes, briaexcavatolides K-N (1-4), along with a known diterpene, 5, have been isolated from the Taiwanese gorgonian Briareum excavatum. The structures of the new metabolites were established by extensive spectral analyses. Furthermore, the structure, including the relative configuration of briaexcavatolide K (1), was confirmed by a single-crystal X-ray analysis. Briaexcavatolides K and L (1 and 2) are the only briarane diterpenes known to possess hydroxyl groups at the C-8beta and C-17alpha positions, respectively. Cytotoxicity of these metabolites toward various cancer cell lines also is described.     

Acanthovagasteroids A-D, four new 19-hydroxylated steroids from the South China Sea gorgonian Acanthogorgia vagae Aurivillius

Four new steroids, acanthovagasteroids A-D (1-4), along with two known analogues (5, 6), were isolated from the gorgonian Acanthogorgia vagae Aurivillius from the South China Sea. The structures of the new compounds, characterized with 19-hydroxy groups, were identified on the basis of extensive spectral analysis as well as by comparison with literature data. This is the first report of 19-hydroxy steroids from a gorgonian and suggests a possible biosynthetic relationship between 19-nor and 19-hydroxy steroids.     

Lemnalosides A-D, decalin-type bicyclic diterpene glycosides from the marine soft coral Lemnalia sp

Four new decalin-type bicyclic diterpenoids, lemnalosides A-D (1-4), along with one known decalin-type bicyclic diterpenoid, lemnabourside (5), were isolated from an extract of the marine soft coral Lemnalia sp. The structures of the new compounds were elucidated on the basis of spectroscopic analysis including 1H-1H COSY, HMQC, HMBC, NOESY, HRESIMS, UV, IR, and chemical means. Compound 1 showed moderate activity in the hyphae formation inhibition (HFI) assay against Streptomyces 85E at a concentration of 20 microg/disk, while compound 2 displayed inhibitory activity in the HFI assay at a concentration of 2.5 microg/disk.