Two new bioactive prenylated dihydroflavanoids from the medicinal plant Dolichos tenuicaulis (Baker) Craib

Two new prenylated dihydroflavanoids have been isolated from the medicinal plant of Dolichos tenuicaulis (Baker) Craib. Their structures were elucidated as (2S)-5,2',6'-trihydroxy-8-prenyl-6,7-(3-prenyl-2,2-dimethylpyrano)-3',4'-(2,2-dimethyl-1-keone-cyclohexadiene)-flavanone (1) and (2S)-5,2',6'-trihydroxy-8-prenyl-6,7-(3-prenyl-2,2-dimethyl-1-keone-cyclohexadiene)-flavanone (2) on the basis of spectroscopic analysis.     

Two new bioactive prenylated dihydroflavanoids from the medicinal plant Dolichos tenuicaulis (Baker) Craib

Two new prenylated dihydroflavanoids have been isolated from the medicinal plant of Dolichos tenuicaulis (Baker) Craib. Their structures were elucidated as (2S)-5,2',6'-trihydroxy-8-prenyl-6,7-(3-prenyl-2,2-dimethylpyrano)-3',4'-(2,2-dimethyl-1-keone-cyclohexadiene)-flavanone (1) and (2S)-5,2',6'-trihydroxy-8-prenyl-6,7-(3-prenyl-2,2-dimethyl-1-keone-cyclohexadiene)-flavanone (2) on the basis of spectroscopic analysis.     

中药苦参主要黄酮类成分的研究

中药苦参为豆科槐属植物苦参Sophora flavescenes Ait.的干燥根，具有清热燥湿、杀虫利尿的功能，主治热痢便血、阴肿阴痒、湿疹、皮肤搔痒，外用治疗滴虫性阴道炎等。黄酮是苦参中一类重要的活性成分，为建立苦参黄酮质量控制方法提供对照品，研究苦参黄酮抗滴虫和抗菌等作用机制和构效关系，首先对其主要黄酮类成分进行了研究，从中分离鉴定了6个主要化合物，分别为5-甲氧基-7，2′,4′-三羟基-8-异戊烯基二氢黄酮(1)、 异黄腐醇(2)、 3β，7，4′-三羟基-5-甲氧基-8-异戊烯基二氢黄酮(3)、 降苦参酮(4)、 苦参酮(5)和苦参醇I(6)。化合物1为新化合物，化合物3为首次从本植物得到，并首次报道了化合物3和5的¹³C NMR数据。     

Two new neolignan glucosides from Arctii Fructus

Two new neolignan glucosides named (7S, 8R)-4,7,9,9′-tetrahydroxy-3,3′-dimethoxyl-7′-oxo-8-4′-oxyneolignan-4-O-β-d-glucopyranoside (1) and (7′S, 8′R, 8S)-4,4′,9′-trihydroxy-3,3′-dimethoxy-7′,9-epoxylignan-7-oxo-4-O-β-d-glucopyranosyl-4′-O-β-d-glucopyranoside (2), together with two small molecular peptides named 3-benzyl-6-(1-hydroxyethyl)-2,5-piperazinedione (3) and 3-benzyl-2,5-piperazinedione (4), were isolated from the extract of Arctii Fructus. Their structures and absolute configurations were elucidated by various spectroscopic methods (IR, HR-ESI-MS, 1D and 2D NMR, and CD).     

Two new xanthones from the stems of Cratoxylum cochinchinense

Two new xanthones, 6-hydroxy-3,7-dimethoxy-8-(3-methylbut-2-enyl)-6′,6′-dimethyl-5′-hydroxy-4′,5′-dihydropyrano(2′,3′:1,2)xanthone (1) and 6-hydroxy-3,7-dimethoxy-8-(2-oxo-3-methylbut-3-enyl)-6′,6′-dimethyl-5′-hydroxy-4′,5′-dihydropyrano(2′,3′:1,2)xanthone (2), have been isolated from the stems of Cratoxylum cochinchinense (Lour.) Blume. Their structures were established on the basis of spectroscopic analysis.     

Two new phthalide dimers from the rhizomes of Ligusticum chuanxiong

Two pairs of diastereoisomers, namely (3′Z)-(3S,8S,3a′S,6′R)-4,5-dehydro-3.3a′,8.6′-diligustilide (1) and (3′Z)-(3S,8R,3a′S,6′R)-4,5-dehydro-3.3a′,8.6′-diligustilide (3), chuanxiongdiolide R3 (2), and chuanxiongdiolide R1 (4), were isolated from the 95% ethanolic aqueous extract of the rhizomes of Ligusticum chuanxiong. Among these Phthalide dimers, compounds 1 and 2 were new ones. The structures of the new isolates were elucidated based on spectroscopic data analyses, and their absolute configurations were determined by comparison of experimental and calculated electronic circular dichroism spectra.     

Flavonoids from the leaves of Pleioblastus argenteastriatus

A new flavonoid, 5,7,3′-trihydroxy-6-C-β-d-digitoxopyranosyl-4′-O-β-d-glucopyranosyl flavonoside (1), along with four known flavonoids 5,7,4′-trihydroxy-3′,5′-dimethoxy flavone (2), 5,3′,4′-trihydroxy-7-O-β-d-glucopyranosyl flavonoside (3), 5,4′-dihydroxy-3′,5′-dimethoxy-7-O-β-d-glucopyranosyl flavonoside (4), 5,3′,4′-trihydroxy-6-C-[β-d-glucopyranosyl-(1 → 6)]-β-d-glucopyranosyl flavonoside (5) were isolated from 95% EtOH extract of the leaves of Pleioblastus argenteastriatus. Their structures were determined on the basis of spectroscopic techniques and chemical methods.     

Flavans from the leaf of Ilex centrochinensis

Phytochemical investigation of the leaf of Ilex centrochinensis led to the isolation and characterization of four flavans, one flavanone (5), and one flavone (6), including a new compound whose structure was elucidated as (2S)-5,3′,4′-trihydroxy-7-methoxyflavan (1) and a new natural product whose structure was elucidated as (2S)-5-hydroxy-7,3′,4′-trimethoxyflavan (4) on the basis of spectroscopic methods especially 1D and 2D NMR, CD, and mass spectral analyses. Compounds 1 and 4 exhibited weak cytotoxic activity against Huh7 cell line and no cytotoxic activity against Caco-2 cell line.     

Chemical Constituents from the Leaves of Magnolia Denudata

Abstract

20 compounds were isolated from the leaves of Magnolia denudata including 16 lignans, which belong to 6 structural types. Except for (7R, 8S, 1′S) -δ^8′ - 1′, 4′ - dihydro - 5′- methoxy - 3, 4 -methylenedioxy - 4′ - oxo -7.O.2′, 8.1′ - neolignan (6), magliflonenone (9), 2,5′ - diene-2′, 8′- epoxy - 5′ - methoxy - 8 - methyl - 4′ - oxo - 3,4-methylenedioxy - spiro (5,5) - undecane (10), veraguensin (16) and β-sitosterol (20), the other 15 compounds were obtained from this species for the first time. The absolute configurations of 3 compounds (1,4,10) were determined by CD spectroscopy for the first time. The anti-inflammatory activities of compounds 1, 2 and 16 were assessed and 2 was shown to have significant inhibition effect on mice hind-paw edema induced by carrageenan.     

One new ergostane-type steroid and three new phthalide derivatives from cultures of the basidiomycete Albatrellus confluens

One new ergostane-type steroid, (12β,15β,22R,23S,24S)-22,25-epoxy-12,15,23-trihydroxyergost-4,6,8(14)-trien-3-one (1), three new phthalide derivatives, 5-(2′,3′-epoxy-3′,3′-dimethylpropoxy)-7-methoxy-6-methylphthalide (2), (2′)-(Z)-5-(3′-hydroxymethyl-3′-methylallyloxy)-7-methoxy-6-methylphthalide (3), and 5-(3′,3′-dimethylallyloxy)-7-hydroxy-6-methylphthalide (4), along with one known phthalide derivative, 5-(3′,3′-dimethylallyloxy)-7-methoxy-6-methylphthalide (5), were isolated from cultures of the basidiomycete Albatrellus confluens. The structures of the new compounds were established on the basis of extensive spectroscopic data (IR, MS, 1D, and 2D NMR) analyses. All compounds were evaluated for their cytotoxic activities on five tumor cell lines.     

红松松针中木脂素类成分的分离与鉴定

目的研究红松松针中的木脂素类成分,为松属植物的化学分类学研究提供依据。方法采用反复硅胶、聚酰胺、ODS、Sephadex LH-20柱色谱等方法进行分离纯化,根据理化性质和波谱分析对分离得到的化合物进行结构鉴定。结果从红松松针中分离得到8个化合物,分别鉴定为(+)-异落叶松脂素-9-O-β-D-吡喃木糖苷((+)-isolariciresinol-9-O-β-D-xylopyranoside,1)、(+)-异落叶松脂素-9-O-β-D-吡喃葡萄糖苷((+)-isolariciresinol-9-O-β-D-glucopyranoside,2)、7S,8R-苏式-3′,4,9′-三羟基-3-甲氧基-7,8-二氢苯并呋喃-1′-丙醇基新木脂素-9-O-α-L-吡喃鼠李糖苷(7S,8R-threo-3′,4,9′-trihydroxy-3-methoxy-4′,7-epoxy-neolignan-9-O-α-L-rhamnopyranoside,3)、7S,8R-苏式-3′,9,9′-三羟基-3-甲氧基-7,8-二氢苯并呋喃-1′-丙醇基新木脂素-4-O-α-L-吡喃鼠李糖苷(7S,8R-threo-3′,9,9′-trihydroxy-3-methoxy-4′,7-epoxy-neolignan-4-O-α-L-rhamnopyranoside,4)、7R,8S-赤式-4,7,9-三羟基-3,3′-二甲氧基-8-O-4′-新木脂素-9′-O-α-L-吡喃鼠李糖苷(7R,8S-erythro-4,7,9-trihydrox-y-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-α-L-rhamnopyranoside,5)、7S,8S-苏式-4,7,9-三羟基-3,3′-二甲氧基-8-O-4′-新木脂素-9′-O-α-L-吡喃鼠李糖苷(7S,8S-threo-4,7,9-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-α-L-rhamnopyranoside,6)、7S,8S-苏式-3′,4,7,9-四羟基-3-甲氧基-8-O-4′-新木脂素-9′-O-α-L-吡喃鼠李糖苷(7S,8S-threo-3′,4,7,9-tetrahydroxy-3-methoxy-8-O-4′-neolignan-9′-O-α-L-rhamnopyranoside,7)、7R,8S-赤式-3′,4,9,9′-四羟基-3-甲氧基-8-O-4′-新木脂素-7-O-β-D-吡喃葡萄糖苷(7R,8S-erythro-3′,4,9,9′-tetrahydroxy-3-methoxy-8-O-4′-neolignan-7-O-β-D-glucopyr-anoside,8)。结论化合物1~8均为首次从红松中分离得到。     

Two novel flavanes from the leaves of Morus alba L.

Two new flavanes, (2R,4S)-2′,4′-dihydroxy-2H-furan-(3″,4″:8,7)-flavan-4-ol (1) and (2S)-2′,4′-dihydroxy-7-methoxyl-8-butyricflavane (2), together with four known flavonoids, were isolated from the leaves of Morus alba L. Their structures were determined on the basis of spectroscopic analysis.     

Four homoisoflavonoids isolated from traditional Chinese medicine: “Gan Luo Xin”

Two new homoisoflavonoids, ( ± )-5,7-dihydroxy-8-methyl-3-(2′,4′-dihydroxybenzyl) chroman-4-one (1) and ( ± )-5,7-dihydroxy-6,8-dimethyl-3-(2′,4′-dihydroxybenzyl) chroman-4-one (2), along with two known homoisoflavonoids, 5,7-dihydroxy-6-methyl-3-(2′,4′-dihydroxybenzyl)chroman-4-one (3) and disporopsin (4), were isolated from the EtOAc extract of traditional Chinese medicine – “Gan Luo Xin.” Their structures were determined on the basis of spectroscopic analysis (UV, IR, HR-ESI-MS, 1D NMR, and 2D NMR).     

Two new dihydrobenzofuran lignans from Rabdosia lophanthoides (Buch.-Ham.ex D.Don) Hara

Two new dihydrobenzofuran lignanosides, (7R,8S)-4,3′,9′-trihydroxyl-3-methoxyl-7,8-dihydrobenzofuran-1′-propylneolignan-9-O-(6-O-syringoyl)-β-d-glucopyranoside, named lophanthoside B (1) and (7R,8S)-4,9,9′-trihydroxyl-3-methoxyl-7,8-dihydrobenzofuran-1′-propylneolignan-3′-O-β-d-glucopyranoside (2), an enantiomer of umbroside, along with four known dihydrobenzofuran lignans (3–6), were isolated from 50% acetone extract of Rabdosia lophanthoides (Buch.-Ham.ex D.Don) Hara. Their structures were elucidated by NMR and MS experiments.     

Geraniinic acid derivative from the leaves of Phyllanthus reticulatus

Chemical constituents as well as cytotoxic and insecticidal activity of the crude methanol extract from the leaves of Phyllanthus reticulatus Poir. (Euphorbiaceae) were investigated. (5R*,6R*)-4,6-Dimethoxycarbonyl-5-[2′,3′,4′-trihydroxy-6′-(methoxycarbonyl) phenyl]-5,6-dihydro-2H-pyran-2-one (1) along with 3,4,3′-tri-O-methylellagic acid, and methyl gallate were isolated from the dichloromethane extract. Determination of their structures was based on spectroscopic analysis. Compound 1 possessed a very weak insecticidal activity against Spodoptera frugiperda (Sf9) with an IC₅₀ value of 27.27?μg/mL.     

Three new C-flavonoids from Corallodiscus flabellata

Three new C-glycosylflavones, named 5,7,4′-trihydroxy-6-methoxy-8-C-[β-d-xylopyranosyl- (1 → 2)]-β-d-glucopyranosyl flavonoside (1), 5,7,4′-trihydroxy-8-methoxy-6-C-[β-d-xylopyranosyl-(1 → 2)]-β-d-glucopyranosyl flavonoside (2), and 5,3′,4′-trihydroxy-7,8-dimethoxy-6-C-[β-d-xylopyranosyl-(1 → 2)]-β-d-glucopyranosyl flavonoside (3), along with two known compounds 5,4′-dihydroxy-7-methoxy-6-C-glucopyranosyl-flavonoside (4), 3-methoxy-4-hydroxymethyl benzoate (5) were isolated from 70% acetone extract of Corallodiscus flabellata. Their structures were identified on the basis of spectroscopic techniques and chemical methods.     

Phenolic compounds from the aqueous extract of Acacia catechu

Two new phenolic compounds, 5-hydroxy-2-[2-(4-hydroxyphenyl) acetyl]-3-methoxylbenzoic acid (1) and (2S,3S)-3,7,8,3′,4′-pentahydroxyflavane (2), were obtained from the aqueous extract of Acacia catechu, along with four known compounds identified as rhamnetin (3), 4-hydroxyphenyl ethanol (4), 3,3′,5,5′,7-pentahydroxyflavane (5), and fisetinidol (6). Their structures were determined on the basis of spectroscopic analysis. Free radical-scavenging activities of the new compounds were evaluated.     

Structural elucidation of a new flavone from Sarcopyramis nepalensis

A novel flavone, named 4′-methoxy-3′,5,7-trihydroxy-8-(1″-(3?,4?,5?-trihydroxyphenyl)ethyl)flavone (1), was isolated from Sarcopyramis nepalensis, along with two known compounds syringaresinol (2) and aralidioside (3). Their structures were established by the spectroscopic analysis, especially by 2D NMR. All of the three compounds were isolated from the plant for the first time.     

Two new chalcones from Clerodendrum phlomidis

Two new chalcones, 3,2′,3′-trihydroxy-4′-methoxychalcone (1) and 3,2′-dihydroxy-4′,6′-dimethoxychalcone (2), were isolated from the seeds of Clerodendrum phlomidis together with three known flavonoids, 5-hydroxy-7-methoxyflavanone (3), 5-hydroxy-7-methoxyflavone (4), and kaempferol-3-O-α-l-rhamnopyranoside (5). The structures of the new compounds 1 and 2 have been established mainly on the basis of 1D and 2D NMR studies.     

New anthraquinone dimer from the root bark of Cassia artemisioides (Gaudich. Ex. DC) Randell

The phytochemical investigation of the root bark of Cassia artemisioides (Gaudich. Ex. DC) Randell resulted in the isolation of one new anthraquinone 1,1′-dihydroxy-3,3′-dimethyl-8,8′-dimethoxy-6,6′-O-bianthraquinone (1) along with four known anthraquinones 1,6-dihydroxy-8-methoxy-3-methylanthraquinone (2), 1-hydroxy-8-methoxy-3-methylanthraquinone (3), 1,8-dihydroxy-6-methoxy-3-methylanthraquinone (4), and 1,6,8-trihydroxy-3-methylanthraquinone (5). The structures of the compounds were elucidated using spectroscopic techniques including 1D and 2D NMR. The compounds were evaluated for antioxidant activity. 1,6,8-Trihydroxy-3-methyl anthraquinone (5) showed good activity among the tested compounds.