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1.
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.  相似文献   
2.
运用红外线分析仪在室外研究了青冈林的能量损耗及其与生理、生态因子的关系.结果表明:能量损耗为2829587.46kJ/(m2·a),其中呼吸能量损耗为76288.06kJ/(m2·a),蒸腾能量损耗为2753249.40kJ/(m2·a).能量损耗以七月份最高.呼吸能量损耗日变化基本上呈“单峰”,其主导因子为温度.但亦出现“午休”,其日变化类型表现为“双峰”曲线.蒸腾能量损耗速率的变化亦有“单峰”、“双峰”和“杂合”三种类型,其主导因子为空气相对湿度.  相似文献   
3.
本文研究了浙江建德山区青冈(Quercus glauca)常绿阔叶林硼含量特征.该地区土壤明显缺硼.优势种青冈干及叶中翻含量随胸径的增大而降低,随冬季的到来而明显增高.较大叶片的硼含量高于较小叶片.育冈干、叶中翻含童明显高于其它常绿伴生种石栋( Lithotarpusglaber)和甜储(Castanopsis tyre).青冈体内较高的翻含量有利于提高其抗寒、抗早能力,并保持其在群落中的优势地位.  相似文献   
4.
A new amide, N‐cis‐sinapoyltyramine ( 1 ), and twelve known compounds were isolated from the aerial parts of Lindera glauca. The structure of the new compound has been established by the study of extensive 2D NMR data.  相似文献   
5.
Seven new and three known bisresorcinols, grevirobstol A (=5,5′‐((6Z,9Z)‐hexadeca‐6,9‐diene‐1,16‐diyl)bisresorcinol; 8 ), 5,5′‐[(8Z)‐hexadec‐8‐ene‐1,16‐diyl]bisresorcinol ( 9 ), and 2‐methyl‐5,5′‐[8Z)‐hexadec‐8‐ene‐1,16‐diyl]bisresorcinol ( 10 ) were isolated from the stems of Grevillea glauca. The new compounds were identified on the basis of spectroscopic data as (Z)‐6,7‐didehydroglaucone A ( 1 ), glaucones A and B ( 2 and 3 , resp.), 2‐(3‐hydroxyisopentyl)bisnorstriatol ( 4 ), 2‐(3‐methylbut‐2‐en‐1‐yl)bisnorstriatol ( 5 ), 2′‐methylgrebustol A ( 6 ), and glaucane ( 7 ).  相似文献   
6.
青冈常绿阔叶林中青冈种群结构与分布格局   总被引:9,自引:0,他引:9       下载免费PDF全文
通过群落与种群的调查,对浙江北部几个地区的青冈常绿阔叶林中青冈种群的数量特征,从分株和分株 萌生枝两个层次上进行了研究.结果表明:青冈种群的大小结构在分株层次上,有两种类型:纺锤形结构和不典型的金字塔形结构(倒“J”型),在分株 萌生枝层次上,都为金字塔形结构;青冈种群主要是集群分布格局;动态分布格局是从集群分布到随机分布.  相似文献   
7.
The composition of essential oil from Artemisia glauca (Asteraceae) growing in southern Siberia was studied. More than 60 oil components consisting of 99.0–99.7% of the total volatile components were identified by GC—MS by comparison of full mass spectra and retention times. The main components of the essential oil were acetylene derivatives of capillene (11–60%) and benzyldiacetylene (1–31%). Other acetylene derivatives such as capillin, (E)-hex-4-en-2-ynylbenzene, 1-(4-methoxyphenyl)-2,4-pentadiyne, and capillarin were also identified in the oil. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 446–449, September–October, 2007.  相似文献   
8.
本文以青冈常绿阔叶林中5种凋落物对对象,研究其分解过程中Ca的释放动态。5种凋落物分解24个月期间Ca浓度总体上呈逐渐增加的趋势,但因干物质的消失,最后Ca还是得到了不同程度的释放,并且Ca浓度和列岛率的变化均很有规律,而不同凋落物的规律并不都一致。Ca浓度和残留率与凋落物干物质列岛率的关系密切,反映了Ca的释放是自身释放和干物质理作用的结果。  相似文献   
9.
Twenty‐eight compounds including seven alkaloids, (+)‐3‐chloro‐N‐formylnornantenine ( 1 ), (+)‐N‐formylnornantenine ( 2 ), (+)‐boldine ( 3 ), (+)‐norboldine ( 4 ), (‐)‐norboldine ( 5 ), lycicamine ( 6 ), and tetrahydroberberine ( 7 ); four flavonoids, kaempferol ( 8 ), kaempferol‐3‐O‐arabinoside ( 9 ), quercetin ( 10 ), and quercetin‐3‐O‐rhamnoside ( 11 ); one butanolide, akolactone A ( 12 ); one p‐quinone, 2,6‐dimethoxy‐p‐quinone ( 13 ); one cyclohex‐2‐en‐1‐one, blumenol A ( 14 ); six benzenoids, methylparaben ( 15 ), p‐hydroxybenzoic acid ( 16 ), vanillic acid ( 17 ), syringic acid ( 18 ), 3,4,5‐trimethoxybenzoic acid ( 19 ), and 3‐(3,4‐dihydroxyphenyl) propionic acid ( 20 ); one diterpene, phytol ( 21 ); one triterpene, squalene ( 22 ); six steroids, (3‐sitosterol ( 23 ), β‐sitostenone ( 24 ), stigmasta‐4,22‐dien‐3‐one ( 25 ), 6β‐hydroxy‐β‐sitostenone ( 26 ), 6β‐hydroxystigmasterone ( 27 ), and β‐sitosteryl‐D‐glucoside ( 28 ) were isolated from the aerial part of Lindera glauca. These compounds were characterized and identified by physical and spectral method. All compounds were isolated for the first time from this plant. Among them, (+)‐3‐chloro‐N‐formylnornantenine ( 1 ) is a new one.  相似文献   
10.
A new dicoumarin, jusan coumarin, (1), has been isolated from Artemisia glauca aerial parts. The chemical structure of jusan coumarin was estimated, by 1D, 2D NMR as well as HR-Ms spectroscopic methods, to be 7-hydroxy-6-methoxy-3-[(2-oxo-2H-chromen-6-yl)oxy]-2H-chromen-2-one. As the first time to be introduced in nature, its potential against SARS-CoV-2 has been estimated using various in silico methods. Molecular similarity and fingerprints experiments have been utilized for 1 against nine co-crystallized ligands of COVID-19 vital proteins. The results declared a great similarity between Jusan Coumarin and X77, the ligand of COVID-19 main protease (PDB ID: 6W63), Mpro. To authenticate the obtained outputs, a DFT experiment was achieved to confirm the similarity of X77 and 1. Consequently, 1 was docked against Mpro. The results clarified that 1 bonded in a correct way inside Mpro active site, with a binding energy of −18.45 kcal/mol. Furthermore, the ADMET and toxicity profiles of 1 were evaluated and showed the safety of 1 and its likeness to be a drug. Finally, to confirm the binding and understand the thermodynamic characters between 1 and Mpro, several molecular dynamics (MD) simulations studies have been administered. Additionally, the known coumarin derivative, 7-isopentenyloxycoumarin (2), has been isolated as well as β-sitosterol (3).  相似文献   
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