Oxanthrone esters from the roots of Cassia kleinii

From the roots of Cassia kleinii two new oxanthrone esters, kleinioxanthrone-3 and kleinioxanthrone-4 have been isolated. Their structures were established as 1,8-dihydroxy-3-methyl-9(10H)-anthracenone-10-oxyhexadecanoate 3 and 2,6,7-trihydroxy-1,8-dimethoxy-3-methyl-9(10H)-anthracenone-10-oxydecanoate 4 respectively based on degradative and spectroscopic evidence.     

Oxanthrone C-glycosides and epoxynaphthoquinol from the roots of Rumex japonicus

Five oxanthrone C-glycosides, namely rumejaposide A-E, and an epoxynaphthoquinol, together with eight known compounds, 2,6-dihydroxy benzoic acid, 4-hydroxy benzoic acid, epicatechin, 4-hydroxy-3-methoxy benzoic acid, 2,6-dimethoxy-4-hydroxyl benzoic acid, rutin, emodin and 2-acetyl-1,8-dihydroxy-3-methyl-6-methoxynaphthalene, were isolated from the roots of Rumex japonicus. The structures of the oxanthrone C-glycosides were elucidated by application of spectroscopic methods as (10R)10-C-beta-glucopyranosyl-1,8,10-trihydroxy-2-carboxyl-3-methyl-9(10H)-anthracenone, (10S)10-C-beta-glucopyranosyl-1,8,10-trihydroxy-2-carboxyl-3-methyl-9(10H)-anthracenone, (10R)10-C-beta-glucopyranosyl-1,6,8,10-tetrahydroxy-2-carboxyl-3-methyl-9(10H)-anthracenone, (10R)10-C-beta-glucopyranosyl-1,6,8,10-tetrahydroxy-3-hydroxymethyl-9(10H)-anthracenone, and (10R)10-C-beta-glucopyranosyl-1,6,8,10-tetrahydroxy-3-methyl-9(10H)-anthracenone. Absolute configurations for each compound were deduced by analyses of CD spectra and comparison with those known similar compounds. The structure of epoxynaphthoquinol was elucidated by spectroscopic methods as 3-acetyl-2-methyl-1,4,5-trihydroxy-2,3-epoxynaphthoquinol, and its relative configuration was determined by a 2D-ROESY experiment.     

Dimeric hydroanthracenes from the unripe seeds of Cassia torosa

From the unripe seeds of Cassia torosa three new dimeric hydroanthracene derivatives were isolated along with stigmasterol, sitosterol, campesterol, physcion-9-anthrone, torosachyrsone and the phlegmacins A₂ and B₂. The structures of the new derivatives were established as physcion-10, 10′-bianthrone, anhydrophlegmacin B₂ [2-(6′-methoxy-3′-methyl-3′, 8′, 9′-trihydroxy-1′-oxo-1′, 2′, 3′, 4′-tetrahydroanthracene-10′-yl)-1, 8-dihydroxy-3-methoxy-6-methyl-9-oxo-9, 10-dihydroanthracene] and torosanin [2-(6′-methoxy-3′-methyl-3′, 8′,9′-trihydroxy-1′-oxo-1′, 2′, 3′,4′-tetrahydroanthracene-5′-yl)-1, 8-dihydroxy-3-methoxy-6-methyl-9-oxo-9, 10-dihydroanthracene], respectively.     

Laurentixanthones A and B, antimicrobial xanthones from Vismia laurentii

A phytochemical investigation of the constituents of the roots of Vismia laurentii has resulted in the isolation of two xanthone derivatives named laurentixanthone A (1) (6-hydroxy-3,3-dimethyl-11-(3-methylbut-2-enyl)pyrano[2,3-c]xanthen-7(3H)-one) and laurentixanthone B (2) (1-hydroxy-5,6,7,8-tetramethoxyxanthone), along with 11 known compounds: 1,7-dihydroxyxanthone, vismiaquinone, vismiaquinone B, bivismiaquinone, 3-geranyloxy-6-methyl-1,8-dihydroxyanthraquinone, O(1)-demethyl-3',4'-deoxypsorospermin-3',4'-diol, 6-deoxyisojacareubin, 1,8-dihydroxy-6-methoxy-3-methylanthraquinone, kaempferol, friedelin and stigmasterol. The structures of compounds were established by means of spectroscopic methods. Furthermore, the compounds were screened for antimicrobial activities in vitro.     

蔓生百部的化学成分研究

从蔓生百部(Stemona japonica)根中分离得到13个化合物,通过波谱数据,它们鉴定为β-谷甾醇(1)、豆甾醇(2)、5,11-豆甾二烯-3β-醇(3)、苯甲酸(4)、4-甲氧基苯甲酸(5)、1,8-二羟基-3-甲基蒽醌(6)、1,8-二羟基-6-甲氧基-3-甲基蒽醌(7)、氧代狭叶百部碱(8)、百部定碱(9)、异狭叶百部碱(10)、绿原酸(11)、栀子苷(12)和藏红花素A(13).所有化合物均为首次从该植物中分离得到.     

Phenanthrenoids from the wetland Juncus acutus

Nine 9,10-dihydrophenanthrenes, three phenanthrenes and a related pyrene have been isolated from the wetland plant Juncus acutus. The structures have been attributed by means of their spectral data and chemical correlation. 5-(1-Ethoxy-ethyl)-2-hydroxy-7-methoxy-1,8-dimethyl-9,10-dihydrophenanthrene and 5-(1-phytoxy-ethyl)-2-hydroxy-7-methoxy-1,8-dimethyl-9,10-dihydrophenanthrene, 2,7-dihydroxy-1-methyl-5-vinylphenanthrene, 2,7-dimethoxy-1,6-dimethyl-5-vinylphenanthrene and 2,7-dihydroxy-1,6-dimethylpyrene are described for the first time. Many of the compounds showed in vitro phytotoxicity against Selenastrum capricornutum, a microalga used in aquatic tests.     

Difuranonaphthoquinones from Plumbago zeylanica roots

The naphthoquinones, lapachol (1), plumbagin (2), 2-isopropenyl-9-methoxy-1,8-di-oxa-dicyclopenta[b,g]naphthalene-4,10-dione (3), 9-hydroxy-2-isopropenyl-1,8-dioxa-dicyclopenta[b,g]naphthalene-4,10-dione (4), 2-(1-hydroxy-1-methyl-ethyl)-9-methoxy-1,8-dioxa-dicyclopenta[b,g]naphthalene-4,10-dione (5) and 5,7-dihydroxy-8-methoxy-2-methyl-1,4-naphthoquinone (6) were isolated isolated from roots of Plumbago zeylanica. The new constituents (3–5) in addition to known compounds (1, 2 and 6) were characterized by spectral analysis (UV, IR, 1D & 2D NMR and MS).     

New antifungal xanthones from the seeds of Rhus coriaria L

Phytochemical investigations of the ethanolic extract of the seeds of Rhus coriaria L. (Anacardiaceae) led to the identification of four new xanthones, characterized as 2,3-dihydroxy-7-methyl xanthone (1), 2,3,6-trihydroxy-7-hydroxymethylene xanthone-1-carboxylic acid (2), 2-methoxy-4-hydroxy-7-methyl-3-O-beta-D-glucopyranosyl xanthone-1,8-dicarboxylic acid (4), and 2-hydroxy-7-hydroxymethylene xanthone-1,8-dicarboxylic acid 3-O-beta-D-glucopyranosyl-(2'-->3")-3"-O-stigmast-5-ene (5), along with the known steroidal glucoside beta-sitosterol-beta-D-glucoside (3). The structures of the isolated compounds have been identified on the basis of spectral data analysis and chemical reactions. All xanthones were active against Aspergillus flavus.     

Post-infectional metabolites from infected potato tubers

The C-1′ epimers of the sesquiterpenoids 2-(1′,2′-dihydroxy-1′-methylethyl)-6,10-dimethylspiro[4,5]dec-6,9-dien-8-one and 2-(1′,2′-dihydroxy-1′-methylethyl)-6,10-dimethyl-9-hydroxyspiro[4,5]dec-6-en-8-one were isolated from potato tubers infected with Phoma foveata and Fusarium spp., in addition to 4,4a,5,6,7-hexahydro-3-hydroxy-6-(1′,2′-dihydroxy-1′-methylethyl)-4-methyl-2(3H)-naphthalenone, N-trans-p-coumaroyl tyramine and N-trans-feruloyl tyramine. Three of the compounds are novel.     

Naphthalenes and naphthoquinones from Ventilago species

Two new naphthalene derivatives and three naphthoquinones have been found in the root bark of Ventilago maderaspatana. Their structures are 2-acetyl-6,7-dimethoxy-3-methyl-1,8-methylenedioxynaphthalene (ventilaginone) and 1,3-dihydro-6,9-dihydroxy-7,8-dimethoxy-1-methylnaphtho[2,3-c]furan-3-one (ventilagol), 2(2′-acetoxypropyl)-3-hydroxy-5,7,8-trimethoxy-1,4-naphthoquinone (maderone), cordeauxione and isocordeauxione. The root bark of V. calyculata contains 2-methoxystypandrone and 1-hydroxy-6-methoxy-3-methylxanthone-8-carboxylic acid (calyxanthone).     

Anthraquinones from Cassia sophera root bark

Two new anthraquinones have been isolated from the root bark of Cassia sophera and characterized as 1,8-dihydroxy-3,6-dimethoxy-2-methyl-7-vinylanthraquinone and 1,3-dihydroxy-5,7,8-trimethoxy-2-methylanthraquinone.     

Synthesis and anti-inflammatory activities of N4,N5-disubstituted-3-methyl- H-pyrazolo[3,4-c]pyridazines

The synthesis and anti-inflammatory activity of 4,5-dihydroxy-3-methyl-1H-pyrazolo[3,4-c]pyridazine (4), 4,5-dichloro-3-methyl-1H-pyrazolo[3,4-c]pyridazine (5), 4,-benzoyloxy-3-methyl-1-benzoyl-1H-pyrazolo[3,4-c]pyridazin-5yl benzoate (6), 3-methyl-N4,N5-bis(4-methylphenyl)-1H-pyrazolo[3,4-c]pyridazine-4,5-diamine (7), 4[[5-(4-carboxyanilino)-3-methyl-1H-pyrazolo[3,4-c]pyridazin-4yl]amino]benzoic acid (8), N-[5-(benzoylamino)-3-methyl-1H-pyrazolo[3,4-c]pyridazin-4-yl]benzamide (9) and 3-methyl-N4,N5-bis[4-(1H-benzimidazol-2yl)phenyl]-1H-pyrazolo[3,4-c]pyridazine-4,5-diamine (10) are being reported.     

Xanthones from the bark of Garcinia merguensis

The bark of Garcinia merguensis yielded 10 xanthones, merguenone, 1,5-dihydroxy-6'-methyl-6'-(4-methyl-3-pentenyl)-pyrano(2',3':3,2)-xanthone, subelliptenone H, 8-deoxygartanin, rheediaxanthone A, morusignin G, 6-deoxyjacareubin, 1,3,5-trihydroxy-4,8-di(3-methylbut-2-enyl)-xanthone, rheediachromenoxanthone and 6-deoxyisojacareubin. The structure of merguenone was determined using spectroscopic techniques, mainly 1D and 2D NMR spectroscopy.     

Starfish saponins—IV. Sapogenins from the starfish Astropecten aurantiacus and Marthasterias glacialis

• 1.1. The major aglycones produced by acid hydrolysis of the saponins from the starfish Astropecten aurantiacus are identified as 3β,6α-dihydroxy-5α-pregn-9(11)-en-20-one (1), (17 E)- and (17 Z)-3β,6α-dihydroxy-5α-cholesta-9(11),17(20)-dien-23-one (9 and 10), (17 E)- and (17 Z)-3β,6α-dihydroxy-5α-cholesta-9(11), 17(20),24-trien-23-one (11 and 12), (20 E)-3β,6α-dihydroxy-5α-cholesta-9(11),20(22)-dien-23-one (4), and 17β-methyl-3β,6α-dihydroxy-18-nor-5α-cholesta-9(11),13-dien-23-one (13).
• 2.2. A re-examination of the sapogenins from the starfish Marthasterias galcialis, in addition to the previously isolated 1, 3β,6α-dihydroxy-5α-cholesta-9(11)-en-23-one (2, dihydromarthasterone), 3β,6αdihydroxy-5α-cholesta-9(11),24-dien-23-one (3, marthasterone) and 3β,6α-dihydroxy-5α-chol-9(11)-en-23-one (14), has shown the presence of minor amounts of 9, 10, 4 and 13.
• 3.3. A [¹³C]NMR study of the major sapogenins, 9 and 10, from A. aurantiacus, and 1, 2 and 14 from M. glacialis is also reported.

     

Thymol derivatives from schizogyne glaberrima

An investigation of Schizogyne glaberrima afforded in addition to known compounds 3-(acetoxy-methyl)-6-methyl-5-methoxy-benzofuran,10-acctoxy-8,9-epoxy-6-methoxy-thymol isobutyrate, 10-acetoxy-8-hydroxy-9-isobutyryloxy-6-methoxy-thymol,8-hydroxy-9,10-isobutyryloxy-thymol and 8,10-dihydroxy-9-isobutyryloxy-thymol, five new thymol derivatives, 8-ethoxy-9-isobutyryloxy-thymol, 10-acetoxy-8,9-dehydro-6-methoxy-thymol isobutyrate, 6-acetoxy-8,9-dehydro-9-carbomethoxy-10-hydroxy-thymol and 8,9-dihydroxy-10-isobutyryloxy-6-methoxy-thymol.     

4-aminophyscion,an anthraquinone derivative from dermocybe (Agaricales)

The anthraquinones physcion, erythroglaucin and 4-aminophyscion (4-amino-1,8-dihydroxy-6-methoxy-3-methyl-9,10-anthraquinone) have been isolated from the fungal species Dermocybe canaria Horak (ined.). 4-Aminophyscion is reported for the first time as a natural product and represents the first fungal anthraquinone with an amino group.     

Geranylated phenolic constituents from the fruits of Artocarpus nobilis

Chemical investigation of the combined dichloromethane and ethyl acetate extracts of the fruits of Artocarpus nobilis, furnished four new geranylated phenolic constituents, 2,4,4'-trihydroxy-3-[(2E)-5-methoxy-3,7-dimethylocta-2,6-dienyl]chalcone (4), 1-(3,4-dihydro-3,5-dihydroxy-2-methyl-2-(3-methyl-2-butenyl)-2H-1-benzopyran-6-yl-3-(4-hydroxyphenyl)-2(E)-propen-1-one (5), 8-geranyl-3',4',7-trihydroxyflavone (8), 3'-geranyl-4',5,7-trihydroxyflavanone (9), together with known related compounds, xanthoangelol (1), xanthoangelol B (2), 3-geranyl-2,3',4,4'-tetrahydroxychalcone (3), lespeol (6), 8-geranyl-4',7-dihydroxyflavanone (7), and isonymphaeol-B (10). Compounds 3, 8 and 10 showed strong antioxidant activity against DPPH radical by spectrophotometric method.     

Cordiachromes from Auxemma oncocalyx

Further cordiachromes, rel-10,11β-epoxy-11-ethoxy-8-hydroxy-2-methoxy-8aβ-methyl-5,6,7,8,8a,9,10aβ-octahydro-1,4-anthracendione, 6-formyl-2-methoxy-9-methyl-7,8-dihydro-1,4-phenanthrendione, rel-8,11;9,11-diepoxy-1,4-dihydroxy-2-methoxy-8aβ-methyl-5,6,7,8,8a,9,10,10aβ-octahydro-10-anthracenone, rel-9,11-epoxy-1,4,8-trihydroxy-2-methoxy-8aβ-methyl-5,6,7,8,8a,9,10,10aβ-octahydro-10-anthracenone, rel-2″-methoxy-7″-methyl-1″,4″-naphtalendione-(6″→5)-tetrahydropyran-(2-eq→O→2ax)-tetrahydropyran-(5′→6)- 2-methoxy-7-methyl-1,4-naphthalendione, together with the known, allantoin, sitosterol and 3β-O-d-glucopyranosylsitosterol, have been isolated from Auxemma oncocalyx. Their structures were determined from spectral data, including 2D NMR experiments.     

Acridone alkaloids from pleiospermium alatum (rutaceae)

The stem of Pleiospermium alatum has yielded two acridone alkaloids, 1,6-dihydroxy-2,3,5-trimethoxy-10-methyl-9-acridone and 1,5-dihydroxy-2,3-dimethoxy-10-methyl-9-acridone. The significance of their occurrence in this genus is discussed.     

Studies on the Compounds Produced by Molds

Three isocoumarin compounds (BV 1, 2 and 3) were isolated from the cultural broth of Aspergillus oniki 1784. BV 1 was mellein (3-methyl-8-hydroxy-3,4-dihydroisocoumarin). BV 2 and 3 were assigned to be 3-methyl-4,8-dihydroxy-3,4-dihydroisocoumarin, 3-methyl-3,8-dihydroxy-3,4-dihydroisocoumarin, respectively. These two compounds (BV 2, 3) were newly isolated. Also another component named BV 4 was proved to be 6-methylsalicylic acid.