The isolation and structure of 6″-bromo-isoarboreol - the first bromine containing lignan

A new lignan from $\text{Gmelina arborea}$ is shown to be 1, 2a-dihydroxy-2e-piperonyl-6e-(6″-bromopiperonyl)-3, 7-dioxabicyclo-[3,3,0]-octane, the first example of a bromine containing lignan.     

Studies on lignan constituents from Schisandra chinensis (Turcz.) Baill. fruits using high-performance liquid chromatography/electrospray ionization multiple-stage tandem mass spectrometry

A reversed-phase high-performance liquid chromatography-diode array detector-electrospray ionization multiple-stage tandem mass spectrometry (RP-HPLC-DAD-ESI-MS(n)) method has been developed for the detection and analysis of lignan constituents in the methanol extract from the fruits of Schisandra chinensis (Turcz.) Baill. RP-HPLC-DAD-ESI-MS(n) and electrospray ionization Fourier transform ion cyclotron resonance multiple-stage tandem mass spectrometry (ESI-FT-ICR-MS(n)) have been applied to investigate the characteristic product ions of four lignan reference compounds. Then, the logical fragmentation pathways of the lignans have been proposed. By comparing the retention time (t(R)) of HPLC, the ESI-MS(n) data and the structures of analyzed compounds with the data of reference compounds and in the literature, 11 peaks in HPLC have been unambiguously identified and another 5 peaks have been tentatively identified or deduced. Also, in the present paper, the extracted ion chromatograms (EIC) have been used to analyze the lignan isomers. The experimental results demonstrate that RP-HPLC-DAD-ESI-MS(n) is a specific and useful method for the identification of the lignan constituents and their isomers.     

Larrealignans A and B, novel lignan glycosides from the aerial parts of Larrea tridentata

Two new lignan glycosides, named larrealignans A (1) and B (2), and a known lignan (3) were isolated from the aerial parts of Larrea tridentata (Zygophyllaceae). The structures of 1 and 2 were determined on the basis of spectroscopic analysis and the results of hydrolytic cleavage. The isolated compounds (1-3) and aglycones (1a, 2a) of 1 and 2 were evaluated for their cytotoxic activities against HL-60 human leukemia cells.     

Asymmetric synthesis of (+)-galbelgin, (-)-kadangustin J, (-)-cyclogalgravin and (-)-pycnanthulignenes A and B, three structurally distinct lignan classes, using a common chiral precursor

The enantioselective synthesis of three structurally distinct classes of lignan from a single, aza-Claisen-derived, chiral morpholine amide is reported. The class of lignan formed is dependent on the substitution pattern in the aryl rings and choice of protecting group on a key benzylic hydroxyl group. The methodology has been used to asymmetrically synthesize and determine the absolute stereochemistry of lignans (+)-cyclogalgravin 3, (-)-pycnanthulignene A 4, (-)-pycnanthulignene B 5, and (-)-kadangustin J 8.     

A new and known cytotoxic aryltetralin-type lignans from stems of Bursera graveolens

A new 4alpha-aryltetralin-type lignan called burseranin (1) and a known analogous lignan picropolygamain (2) were isolated along with known triterpenes, lupeol and epi-lupeol from the methanol extract of stems of Bursera graveolens, which showed a remarkable inhibitory activity against human HT1080 fibrosarcoma cells. The whole structure of 1 was established based on combined spectral studies and the absolute structure for 2 was first confirmed by CD spectral evidence. In addition, cytotoxic activities of the stem (methanol) extract and its components are evaluated in this paper.     

Determination of mammalian lignans in biological samples by modified gas chromatography/mass spectrometry

Lignans in flaxseed have been part of the human diet for centuries. In 1955, the isolation and structure of the lignan derivative secoisolariciresinol diglucoside (SDG) was reported. The biological role of SDG and mammalian lignan metabolites enterodiol and enterolactone was initially reported 20 years later. Experimental evidences showed the beneficial effects of lignans on breast, colon, and thyroid cancer. A modified gas chromatography/mass spectrometry (GC/MS) assay was developed for lignans in serum and colon samples of rats fed flaxseed meal. The method developed for the analysis of metabolites involves extraction and derivatization of samples and quantitative analysis by selected ion monitoring using GC/MS. The levels of lignan metabolites enterodiol and enterolactone were determined to be 0.013 and 0.23 microM in serum samples and 0.008 and 1.63 microM in colon samples.     

翼梗五味子的研究 V: 五脂素A1, A2, 表五脂A1和epischisandrone的结构

从四川宜宾产翼梗五味子的果实中分得七个四氢萘木脂素, 其中三个鉴定为: 恩施辛enshicine, 表恩施辛epienshicine和schisandrone, 其余四个均属新化合物, 命名为五脂素wnlignan A1, 五脂素A2, 表五脂素epiwnlignan A1和epischisandrone. 它们的结构(包括绝对构型)由光谱分析和化学转化为(+)-dimethylguaiacine和(-)-dimethylisoguaiacine而阐明. 四个新化合物皆有不同程度的体外抗癌活性.     

Determination of lignans in flaxseed using liquid chromatography with time-of-flight mass spectrometry

A new method of flaxseed-derived lignan determination was developed using HPLC with high-resolution time-of-flight MS (TOF-MS), optimized, and compared to two existing methods (HPLC/MS/MS and GC/MS). The limits of detection (LODs) for HPLC/TOF-MS (0.002–0.043 pg) were comparable with those of the optimized and improved HPLC/MS/MS (0.001–0.015 pg), whereas the LODs for the optimized GC/MS were higher (0.02–3.0 pg, yet lower than reported before). Using the newly developed detection and separation methods, several key flaxseed sample preparation parameters (including extraction, hydrolysis, and sample purification) were evaluated resulting in the development of efficient protocol for lignan quantification from flaxseed hulls and embryos. The results confirmed the importance of quantification of both aglycones and unhydrolyzed glucosides in order to obtain the total lignan estimates.     

Three New Lignan Derivatives from Lindera glauca (Siebold et Zucc.) Blume

Two new aryl‐tetralin lignan glycosides, linderanosides A and B ( 1 and 2 , resp.), and a new dihydrobenzofuran neolignan glycoside, linderanoside C ( 3 ), together with five known lignan derivatives ( 4 – 8 ) were isolated from the trunk of Lindera glauca. The structures of these new compounds were determined through spectroscopic analyses, including extensive 2D‐NMR data and acid hydrolysis. The absolute configurations of the compounds were clarified by circular dichroism (CD) spectroscopic studies. Compounds 1 – 8 were evaluated for their cytotoxicity against A549 (non‐small cell lung adenocarcinoma), SK‐OV‐3 (ovarian cancer cells), A498 (human kidney epithelial cells), and HCT‐15 (colon cancer cells) human tumor cell lines using sulforhodamine B assays in vitro.     

Lignans and Alkaloids from Haplophyllum suaveolens

Summary.  A new lignan of the dibenzylbutyrolactone type, haplotonin, was isolated from the aerial parts of Haplophyllum suaveolens together with five known compounds-the alkaloids flindersine, 6-methoxyflindersine, N-acetoxymethylflindersine, and evoxine and the lignan 4-acetyldiphyllin. This is the first report on the occurrence of N-acetoxymethylflindersine in the genus Haplophyllum and on 6-methoxyflindersine and 4-acetyldiphyllin as constituents of the investigated species. Received August 10, 1999. Accepted (revised) October 12, 1999     

Chemical Constituents from Acanthopanax senticosus and Their Cytotoxic Activities

Chemistry of Natural Compounds - A new lignan, named 1,6-bis-(3-methoxy-4-hydroxyphenyl)hexane-1,6-dione (1), together with seven known compounds (2–8) were isolated from the EtOAc-soluble...     

A New Lignan and Four New Lignan Glycosides from Mananthes patentiflora

A new lignan, 5‐hydroxyjusticidin A (= 9‐(1,3‐benzodioxol‐5‐yl)‐5‐hydroxy‐4,6,7‐trimethoxynaphtho[2,3‐c]furan‐1(3H)‐one; 1 ), and four new diphyllin‐type lignan glycosides, mananthosides C–F ( 2 – 5 ), containing glucosyl (Glc), arabinosyl (Ara), galactosyl (Gal), and/or apiosyl residues, have been isolated from Mananthes patentiflora, together with five known compounds. Their structures and configurations were elucidated by in‐depth 1D‐ and 2D‐NMR experiments, as well as MS analysis.     

A New Lignan,Cagayanin, from Nutmeg of Myristica Cagayanensis Merr

A new lignan, cagayanin, has been isolated from the nutmeg of Myristica cagayanensis Merr. and elucidated as formula (5) by spectral and chemical evidence.     

超分子有序聚集凝固液相微萃取及其对五味子中木脂素类化合物的测定及质量评价

通过分析比较漂浮有机液滴凝固液相微萃取(SFODLPME)对木脂素类化合物萃取前后紫外光谱的变化, 提出了超分子有序聚集凝固液相微萃取(SSMOALPME)机理; 建立了简单、 快速、 灵敏的SSMOALPME高效液相色谱法(HPLC)同时测定中药五味子中5种低丰度木脂素类化合物含量的方法, 并对不同产地五味子的质量进行比较和评价. 在最佳的SSMOALPME条件下, 测得五味子醇甲, 五味子酯甲, 五味子甲素, 五味子乙素和五味子丙素的线性范围分别为2.48×10^-3~6.21, 2.27×10^-3~28.5, 2.31×10^-3~28.8, 2.27×10^-3~5.69和1.05×10^-3~5.25 μg/mL; 检出限分别为0.4, 0.4, 0.4, 0.08和0.08 ng/mL; 日内及日间精密度RSD<9.7%; 药材中分析物的回收率为91.9% ~104.7%; SSMOALPME对5种分析物的富集倍数分别在39 ~529倍之间. 本法测定结果与药典法测定结果相比无显著差异(P=95%). SSMOALPME方法的提出为液相微萃取的理论研究奠定了基础, 为反映中药多成分、 多靶点及协同作用的特性, 建立科学的质量控制方法提供了理论依据和实验基础.     

A New Lignan,Formosanol, from Juniperus Formosana

A new lignan, formosanol, has been isolated from Juniperus formosana Hayata and elucidated as formula (5a) by spectra and chemical evidences.     

Isolation and Characterization of Anti-Inflammatory Lignans from Oenanthe javanica

Chemistry of Natural Compounds - A new lignan, named 1-phenylpropenoate-4,8′-lignan A (1), and three known lignans (2–4) were isolated from Oenanthe javanica (Blume) DC. for the first...     

A New Lignan from Gymnotheca involucrata

Chemistry of Natural Compounds - A new lignan, named gymnotheinvolin (1), and three known compounds (2–4) were isolated from the Chinese medicinal plant Gymnotheca involucrata. The structure...     

Taiwanin H,A New Lignan from the Barks of Taiwania Cryptomerioides Hayata

A new lignan, taiwanin H, has been isolated from the barks of Taiwania cryptomerioides Hayata and elucidated as formula ( 6a ) by chemical and physical evidence.     

The Synthesis of a Novel Lignan

Lignans have attracted much interest over the years on account of their widespread ocurrence in nature1, and on account of their broad range of biological activity2. Thus, several lignans are known to exhibit anti-tumor activity3-7, while others function as growth inhibitors and antifungal agents8,9. The importance is the isolation of lignans from animals, including human beings10-12, which has led to the suggestion that such compounds may be an example of a novel class of hormone controlling …     

Two New Glycosides from Rubus amabilis

Rubus amabilis Focke is a shrub which widely spread in China. Its fruits are often processed into health drinks. Its roots, branches and leaves have fairly good medical values1. No phytochemical examination on the plant has been reported up to now. Two new glycosides were obtained from this plant. To our knowledge, they are the first C21-steroid and the first lignan isolated from the genus Rubus.Compound 1 was obtained as a white amorphous powder, mp: 290-292oC, [(]D20 110 (c 0.25, pyridi…