Three isoflavanones with cannabinoid-like moieties from Desmodium canum

Three further derivatives of 5,7,2',4'-tetrahydroxy-6-methyl isoflavanone have been isolated from the root extract of Desmodium canum and assigned the structures 2,3-dihydro-5,7-dihydroxy-6-methyl-3-(1a,2,3,3a,8b,8c-hexahydro-6-hydroxy-1,1,3a-trimethyl-1H-4-oxabenzo[f]cyclobut[c,d]inden-7-yl)-4H-1-benzopyran-4-one (1) 2,3-dihydro-5,7-dihydroxy-6-methyl-3-(6a,7,8,10a-tetrahydro-3-hydroxy-6,6,9-trimethyl-6H-dibenzo[b,d]pyran-2-yl)-4H-1-benzopyran-4-one (2) 2,3-dihydro-5,7-dihydroxy-6-methyl-3-(3-hydroxy-6,6,9-trimethyl-6H-dibenzo[b,d]pyran-2-yl) 4H-1-benzopyran-4-one (3). The three compounds and the previously isolated chromene 4 all derive from the geranylated precursor 5 by a series of cannabinoid-like oxidative rearrangements.     

观光木酚性成分研究

从观光木(Tsoongiodendron odorum Chun)茎枝的80％乙醇提取物中分离得到11个酚性化合物,经波谱鉴定为:对羟基苯甲醛(1)、香草醛(2)、1,3,5-三甲氧基苯(3),丁香醛(4)、香草酸(5)、苏式-2,3-二-(4-羟基-3-甲氧基苯)-3-甲氧基丙醇(6)、赤式-2,3-二-(4-羟基-3-甲氧基苯)-3-甲氧基丙醇(7)、丁香酸(8)、3-羟基-1-(4-羟基-3,5-二甲氧基苯)-1-丙酮(9)、对羟基苯乙醇(10)和C-veratroylglycol( 11).其中,化合物1～4和6～ 11为首次从该植物中分离得到.     

云南铁杉中一个新的倍半木脂素

从云南铁杉(Tsuga dumosa) 心材中分离得到9 个化合物, 采用波谱方法鉴定了它们的结构。其中化合物1 (3 (4 hydroxy 3 methoxy benzyl ) 5 [2 (4 hydroxy 3 methoxy phenyl ) 3 hy droxymethyl 7 methoxy 2, 3 dihydro benzofuran 5 yl] 4 hydroxymethyl dihydro furan 2 one) 为一个新的倍半木脂素, 命名为dumosaol, 2~9为首次从该种植物中分离得到。     

New Phenylpropanoid Glycosides from Illicium majus and Their Radical Scavenging Activities

Chemical investigation of the ethanol extract of the branch and leaves of Illicium majus resulted in the isolation of four new phenylpropanoid glycosides ( 1 – 4 ) and one new phenolic glycoside ( 9 ), along with 13 known ones. Spectroscopic techniques were used to elucidate the structures of the new isolates such as 3-[(2R,3S)-7-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-2,3-dihydro-1-benzofuran-5-yl]propyl β-D-glucopyranoside ( 1 ), [(2R,3S)-7-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropyl)-2,3-dihydro-1-benzofuran-3-yl]methyl 2-O-α-L-rhamnopyranosyl-β-D-glucopyranoside ( 2 ), [(2R,3S)-7-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropyl)-2,3-dihydro-1-benzofuran-3-yl]methyl 2-O-α-L-rhamnopyranosyl-β-D-xylopyranoside ( 3 ), 3-[(2R,3S)-3-({[2-O-(4-O-acetyl-α-L-rhamnopyranosyl)-β-D-xylopyranosyl]oxy}methyl)-7-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-2,3-dihydro-1-benzofuran-5-yl]propyl acetate ( 4 ), and 4-(2-hydroxyethyl)phenyl 3-O-β-D-glucopyranosyl-β-D-glucopyranoside ( 9 ). Free radical scavenging activities of the isolates were elucidated through the DPPH assay method. The most active compounds, 1-O-caffeoyl-β-D-glucopyranose ( 17 ) and soulieana acid 1 ( 18 ), exhibited moderate radical scavenging activities (IC₅₀=37.7±4.4 μM and IC₅₀=97.2±3.4 μM, respectively). The antibacterial activities of the isolates against Staphylococcus aureus and Escherichia coli were also assessed, and no activity was shown at the measured concentration (<32 μg/mL).     

Metabolites from the endophytic fungus Xylaria sp. PSU-D14

Glucoside derivatives, xylarosides A (1) and B (2), were isolated from the broth extract of the endophytic fungus Xylaria sp. PSU-D14 along with two known compounds, sordaricin (3) and 2,3-dihydro-5-hydroxy-2-methyl-4H-1-benzopyran-4-one (4). The structures were assigned by spectroscopic methods. Sordaricin (3), one of the known metabolites, exhibited moderate antifungal activity against Candida albicans ATCC90028 with a MIC value of 32 microg/ml.     

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.     

金黄喇叭菌中一个新的炔酸化合物

从担子菌金黄喇叭菌(CratereUus aureus)子实体中分离到3个炔酸类化合物,其中-个为新化合物,其化学结构通过波谱学方法和量子化学计算鉴定为(8E,10R,14Z)-10-羟基-8,14-十八碳二烯-12-炔酸(1).     

Neoflavonoids and the cinnamylphenol kuhlmannistyrene from Machaerium kuhlmannii and M. Nictitans

The trunkwood of Machaerium kuhlmannii contains methyl palmitate, 3-O-acetyloleanolic acid and sitosterol; the benzene derivatives 2,3-dimethoxyphenol, 2,6-dimethoxyphenol, 2-hydroxy-3-methoxyphenol, 2,3-dimethoxybenzaldehyde and methyl 3-(2-hydroxy-4-methoxyphenyl)-propionate; the isoflavonoids formononetin and (6aS,11aS)-medicarpin; the neoflavonoids (R)-3,4-dimethoxydalbergione, (R)-3,4-dimethoxydalbergiquinol, kuhlmanniquinol [(R)-3-(4-hydroxyphenyl)-3-(5-hydroxy-2,3,4-trimethoxyphenyl)-propene], dalbergin, kuhlmannin (6-hydroxy-7,8-dimethoxy-4-phenylcoumarin) and kuhlmannene (6-hydroxy-7,8-dimethoxy-4-phenylchrom-3-ene), as well as the cinnamylphenol kuhlmannistyrene [Z-1-(5-hydroxy-2,3,4-trimethoxybenzyl)-2-(2-hydroxyphenyl)-ethylene]. Five of these compounds, in addition to (R)-4′-hydroxy-3,4-dimethoxydalbergione, were also isolated from a trunkwood extract of M. nictitans. Structural assignments were confirmed by chemical interconversion and by the synthesis of (±)-kuhlmanniquinol.     

Seco diterpenoids from Excoecaria agallocha L

Chemical examination of the ethyl acetate solubles of the CH(3)OH:CH(2)Cl(2) (1:1) extract of the roots of Excoecaria agallocha L. collected from Godavary estuary resulted in the isolation of three more new diterpenoids, agallochins M-O (1-3). The structures of the new diterpenoids were elucidated by a study of their physical and spectral data as methyl ent-13-epi-8,13-epoxy-4,6alpha-dihydroxy-3,4-secolabd-14-en-3-oate (1), methyl ent-13-epi-8,13-epoxy-2,3-secolabd-14-en-2,11-olid-3-oate (2), and methyl ent-17-hydroxy-3,4-secokaura-4(19),15-dien-3-oate (3).     

Champanones, yellow pigments from the seeds of champa (Campomanesia lineatifolia)

Chemical investigation of the methanol extract of the seeds of Campomanesia lineatifolia Ruiz and Pav. (Myrtaceae) led to the isolation of two new beta-triketone type compounds, named champanones A (1) and B (2), together with the known 2,3-dihydro-5-hydroxy-6,8,8-trimethyl-2-phenyl-4H-1-benzopyran-4,7(8H)-dione (champanone C) (3). The structures of 1 and 2 were determined to be 2,2,4,4-tetramethyl-6-(1-oxo-3-phenylprop-2-enyl) cyclohexane-1,3,5-trione (occurs as an enol form) and 2,2,4-trimethyl-6-(1-oxo-3-phenylprop-2-enyl)cyclohexane-1,3,5-trione (occurs as an enol form), respectively, by means of spectroscopic analysis. The three compounds showed mild antimicrobial activity.     

Alkaloids from Portulaca oleracea L

Five alkaloids (oleraceins A, B, C, D and E) were isolated from Portulaca oleracea L., and their structures determined by spectroscopic methods as 5-hydroxy-1-p-coumaric acyl-2,3-dihydro-1H-indole-2-carboxylic acid-6-O-beta-D-glucopyranoside, 5-hydroxy-1-ferulic acyl-2,3-dihydro-1H-indole-2-carboxylic acid-6-O-beta-D-glucopyranoside, 5-hydroxy-1-(p-coumaric acyl-7'-O-beta-D-glucopyranose)-2,3-dihydro-1H-indole-2-carboxylic acid-6-O-beta-D-glucopyranoside, 5-hydroxy-1-(ferulic acyl-7'-O-beta-D-glucopyranose)-2,3-dihydro-1H-indole-2-carboxylic acid-6-O-beta-D-glucopyranoside and 8,9-dihydroxy-1,5,6,10b-tetrahydro-2H-pyrrolo[2,1-a]isoquinolin-3-one, respectively.     

干花豆中的三个异戊烯基黄烷酮

从滇产干花豆（Fordia cauliflora Hemsl.）茎的乙醇提取物中首次分离得到5个化合物,通过理化及波谱分析,它们分别确定为羽扇豆醇（1）、8,8-dimethyl-2-phenyl-10-prenyl-2,3-dihydro-8H-pyrano[3,2-g]chroman-4-one（2）、7-羟基-6,8-二异戊烯基黄烷酮（3）、7-甲氧基-8-异戊烯基黄烷酮（4）和齐墩果酸（5）.     

Phytotoxic naphthopyranone derivatives from the coprophilous fungus Guanomyces polythrix.

Reinvestigation of the fermentation broth and mycelium of the coprophilous fungus Guanomyces polythrix, grown in static conditions, led to the isolation of several phytotoxic compounds, including two new naphthopyranone derivatives, namely (2S, 3R)-5-hydroxy-6,8-dimethoxy-2,3-dimethyl-2,3-dihydro-4H-naphtho[2,3-b]-pyran-4-one and (2S, 3R)-5-hydroxy-6,8,10-trimethoxy-2,3-dimethyl-2,3-dihydro-4H-naphtho[2,3-b]-pyran-4-one. The structures of the new compounds were established by spectral and chiroptical methods. In addition, the structure of 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ester was unambiguously determined by X-ray analysis. The isolates caused significant inhibition of radicle growth of two weed seedlings (Amaranthus hypochondriacus and Echinochloa crusgalli) and interacted with both spinach and bovine brain calmodulins.     

Characterisation and X-ray crystallography of products from the Bucherer-Bergs reaction of methyl 2,3-O-isopropylidene-alpha-D-lyxo-pentodialdo-1,4-furanoside

Methyl 2,3-O-isopropylidene-alpha-D-mannofuranosidurononitrile [alternative name: methyl (5R)-5-C-cyano-2,3-O-isopropylidene-alpha-D-lyxofuranoside] (2), methyl 2,3-O-isopropylidene-alpha-D-mannofuranosiduronamide [methyl (5S)-5-C-carbamoyl-2,3-O-isopropylidene-alpha-D-lyxofuranoside; methyl (5S)-2,3-O-isopropylidene-alpha-D-lyxo-hexofuranosiduronamide] (3), methyl 2,3-O-isopropylidene-alpha-D-mannofuranosiduronic acid [methyl (5S)-2,3-O-isopropylidene-alpha-D-lyxo-hexofuranosiduronic acid] (4), methyl 5-deoxy-2,3-O-isopropylidene-5-ureido-beta-L-gulofuranosiduronamide [methyl (5R)-5-deoxy-2,3-O-isopropylidene-5-ureido-alpha-D-lyxo-hexofuranosiduronamide (5), and (4S,5S,6R)-5,6-dihydro-6-hydroxy-4,5-isopropylidenedioxy-4H-pyrido[2,1-e]imidazolidine-2',4'-dione [IUPAC name: (3aS,4R,8aS)-4-hydroxy-2,2-dimethyl-3a,8a-dihydro-4H-1,3-dioxa-4a,6-diaza-s-indacene-5,7-dione] (6), instead of the expected hydantoin derivative, were obtained from the Bucherer-Bergs reaction of methyl 2,3-O-isopropylidene-alpha-D-lyxo-pentodialdo-1,4-furanoside (1). The structure of 6 was deduced from NMR and mass spectral data and confirmed by X-ray crystallography. The configuration at C-5 in 2-5 was confirmed by establishing the 5S configuration of 3 by X-ray crystallography. Conformations of the six- and five-membered rings in 3 and 6 are also discussed.     

Chemical constituents of Polygala tenuifolia roots and their inhibitory activity on lipopolysaccharide-induced nitric oxide production in BV2 microglia

A methanolic extract of the roots of Polygala tenuifolia (Polygalaceae) significantly attenuated nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated BV2 microglia cells. Five xanthones, 1-hydroxy-7-methoxyxanthone (1), 3,6-dihydroxy-1,2,7-trimethoxyxanthone (2), 1,3,6-trihydroxy-2,7-dimethoxyxanthone (3), 1,7-dihydroxy-2,3-dimethoxyxanthone (4) and 1,7-dihydroxy-3-methoxyxanthone (5), and five phenylpropanoids, 4-hydroxy-3-methoxypropiophenone (6), methyl 4-hydroxy-3-methoxycinnamic acid (7), 3,4,5-trimethoxycinnamic acid (8), 4-methoxycinnamic acid (9) and β-d-(3-O-sinapoyl) fructofuranosyl-α-d-(6-O-sinapoyl)glucopyranoside (10), were isolated from CHCl(3) fraction using bioactivity-guided fractionation. Among these compounds, compounds 1, 2, 4, 5 and 7 showed significant inhibitory effects on LPS-induced NO production in BV2 microglia cells at the concentration ranging from 10.0 to 100.0 μM.     

Eudesmanes from Pluchea sagittalis. Their antifeedant activity on Spodoptera frugiperda

Eudesmane-type sesquiterpenoids 3-(2,3-epoxy-2-methylbutyryloxy)-4-formoxy-11-hydroxy-6,7-dehydroeudesman-8-one (1) and 3-(2,3-epoxy-2-methylbutyryloxy)-4,7,11-trihydroxyeudesman-8-one (2), together with 10 known structurally related eudesmanes were isolated from the CHCl₃ extract of aerial parts of Pluchea sagittalis (Lamarck) Cabrera. Their structures were deduced by extensive application of 1 and 2D NMR spectroscopic techniques and high and low resolution CIMS. X-ray crystallographic analysis of the known compound 3-(2,3-epoxy-2-methylbutyryloxy)-4-formoxycuauthemone (9) is reported here for the first time, and confirms the structural features for the series of the reported eudesmanes. All eudesmanes were tested for their antifeedant activity by incorporating them to an artificial diet of larvae of the polyphagous insect Spodoptera frugiperda at a concentration of 100 ppm. Our results, from feeding choice tests, indicated that most of the compounds deter larval feeding at the cited concentration.     

Eleutherinone,a novel fungitoxic naphthoquinone from Eleutherine bulbosa (Iridaceae)

The dichloromethane extract prepared from the underground parts of Eleutherine bulbosa (Miller) Urban (Iridaceae) showed strong activity in the direct bioautography assay with the phytopathogenic fungus Cladosporium sphaerospermum. This assay was used to guide the fractionation of this extract and allowed the isolation of four compounds: the new naphthoquinone eleutherinone[8-methoxy-1-methyl-1,3-dihydro-naphtho(2,3-c)furan-4,9 -dione] and the known compounds, previously isolated from this species, eleutherin [9-methoxy-1(R),3(S)-dimethyl-3,4-dihydro-1H-benzo(g)isochromene-5,10-dione], isoeleutherin [9-methoxy-1(R),3(R)-dimethyl-3,4-dihydro-1H-benzo(g)isochromene-5,10-dione], and eleutherol [4-hydroxy-5-methoxy-3(R)-methyl-3H-naphtho(2,3-c)furan-1 -one]. All quinonoid compounds showed strong antifungal activity in the bioautography assay at 100 g/spot, while eleutherol was inactive.     

Chromenes from Peperomia serpens (Sw.) Loudon (Piperaceae)

Chromatographic separation of the CH2Cl2 extract from leaves of Peperomia serpens yielded two chromenes [5-hydroxy-8-(3',7'-dimethylocta-2',6'-dienyl)-2,2,7-trimethyl-2H-1-chromene (1) and 5-hydroxy-8-(3'-methyl-2'-butenyl)-2,2,7-trimethyl-2H-1-chromene-6-carboxylic acid (2)], besides the known chromene [methyl 5-hydroxy-2,2,7-trimethyl-2H-1-chromene-6-carboxylate (3)] and the flavonoid, dihydrooroxylin (4). Their structural elucidation were achieved by spectroscopic analyses. The antifungal activities of the CH2Cl2 extract and the isolated chromenes were measured bioautographically against Cladosporium cladosporioides and C. sphaerospermum, when it was found that the crude extract showed higher activity as compared to the pure compounds.     

Three new triterpenoids from Potentilla multicaulis

Three new triterpenoids, 19-hydroxy-2,3-secours-12-ene-2,3,28-trioic acid 3- methyl ester (1), 19-hydroxy-1-oxo-2-nor-2,3-secours-12-ene-3,28-dioic acid (2), and (3beta,18alpha,19alpha)-3,28-dihydroxy-20,28-epoxyursan-24-oic acid (3), were isolated from the roots of Potentilla multicaulis. Their structures were elucidated on the basis of spectroscopic methods (IR, HR-ESI-MS, and 1D- and 2D-NMR). Compound 2b exhibited moderate cytotoxic activity against human promyelocytic leukemia (HL-60) cells.     

Flavonoids and isoflavonoids from Gynerium sagittatum

Four flavonoids namely (2R,3R)-2,3-trans-7,4'-dimethoxydihydroflavonol, (2R,3S,4S)-2,3-trans-3,4-cis-7,4'-dimethoxy-3,4-flavandiol, 6-hydroxy-7,4'-dimethoxyflavone, 6,7,4'-trimethoxyflavone, along with the known isoflavonoids ferreirin, dihydrocajanin, dalbergioidin, dihydrobiochanin A and biochanin A and other 11 known compounds were isolated from the roots of Gynerium sagittatum. The structural characterization of these compounds was carried out via one- and two-dimensional NMR experiments in combination with ESI-MS. Finally a quantitative analysis of the isoflavones of the methanolic extract was performed by LC-ESI-MS. The high quantity of isoflavonoids found in G. sagittatum makes this plant a good natural source of isoflavonoids.