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11.
A new compound was elucidated as 9-acetyl-6-caryophyllen-15-ol. Iridoid glucosides including catalpol, methyl catalpol, 7-deoxy-8-epiloganic acid, and aucubin, were isolated from leaves of Buddleia parviflora, while the known compounds were identified as dehydrobuddledin A and buddledin C. The structures was elucidated by extensive 1D-2D-NMR spectroscopy. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 29–31, January–February, 2008.  相似文献   
12.
The essential oil of aerial parts of Stachys acerosa, which belongs to the Lamiaceae family and grows in central Iran, was obtained by a hydrodistileation method and analyzed by GC and GC-MS apparatus. Fourteen compounds representing 98.8% of the oil were identified. Among them N-methylisatin (30%), α-pinene (25%), sabinene (12.3%), and 2-hydroxyacetophenone (11.2%) were the major constituents of the oil, which was obtained in 0.1% yield. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 32–34, January–February, 2007.  相似文献   
13.
The composition of the essential oil obtained by hydrodistillation from the leaves of Stachys schtschegleevii Sosn. before the flowering stage was analyzed by GC and GC-MS. Forty-five compounds representing 98.7% of the total oil were identified, of which α-pinene (36.4%), germacrene-D (18.6%), limonene (8.2%), and piperitone (6.2%) were the major constituents. Furthermore, antibacterial activity of the entire oil and its two main monoterpenes was evaluated against six Gram-positive and Gram-negative bacteria. The oil exhibited moderate activity against the tested bacteria.__________Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 138–140, March–April, 2005.  相似文献   
14.
天女木兰油的分析鉴定   总被引:7,自引:0,他引:7  
季怡萍  杨振华 《分析化学》1993,21(4):419-421
本文采用色谱质谱法分析了天女木兰油的化学成份,共鉴定出二十个组份,并对所得结果进行了讨论。  相似文献   
15.
A simple and eco‐friendly procedure has been devised for the green synthesis of palladium nanoparticles, using the aqueous extract of herbal tea (Stachys lavandulifolia), a renewable and nontoxic natural phyto‐exudate. The water‐soluble components of the extract act as reducing agent and stabilizer. This green route does not require a surfactant or capping agent for the growth of palladium nanoparticles. The generated nanoparticles were analysed using UV–visible spectroscopy, transmission electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X‐ray analysis and inductively coupled plasma. The palladium nanoparticles having spherical shape and dimensions of between 5 and 7 nm were employed as a homogeneous catalyst for Suzuki coupling reactions conducted in water under mild conditions. Good yields of products, a facile work‐up, no evidence of leached palladium from the catalyst surface and smooth recovery of the catalysis by adding ethyl acetate, which could be reused at least eight times, confirm the very good efficiency of the catalytic reaction. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
16.
A new rosane-type diterpenoid (1) has been isolated from the chloroform fraction of Stachys parviflora. Structure of 1 was proposed based on 1D and 2D NMR techniques including correlation spectroscopy, heteronuclear multiple quantum coherence, heteronuclear multiple bond correlation and nuclear Overhauser effect spectroscopy. A theoretical model for the electronic and spectroscopic properties of compound 1 is also developed. The geometries and electronic properties were modelled at B3LYP/6-31G* and the theoretical scaled spectroscopic data correlate nicely with the experimental data.  相似文献   
17.
A new derivative of syringic acid, stageobester A (1) and two iridoid glycosides which including a new one, stageoboside A (2), were isolated from the roots of Stachys geobombycis. Their structures were elucidated on the basis of spectroscopic methods, including extensive NMR and MS spectra. In addition, all the isolates were tested for their antioxidant capacity. Compounds 1 and 2 showed moderate antioxidant activities against DPPH radical, with IC50 values of 113.33 ± 1.53 and 40.33 ± 2.08 mg/L, respectively.  相似文献   
18.
The fumigant toxicity of Xylopia parviflora (A. Rich.) Benth (Annonaceae) root bark's essential oil (EO) against cowpea seed bruchid, Callosobruchus maculatus, was investigated in the laboratory. Dose had significant (P < 0.0001) effect on mortality at 6 hours after treatment (HAT) at a concentration of 6.25 μL/mL air which exerted 81.70% mortality, while there was no mortality in all other lower doses. At 12 HAT, 75.05% and 90.00% mortality were observed at doses of 3.15 and 6.25 μL/mL air, respectively. It was significantly (P < 0.05) higher than the mortality (50.58%) observed when 0.78 μL/mL air was applied. The lethal time for 50% of assayed adults (LT50) obtained when the bruchid was exposed to X. parviflora EO at a dose of 6.25 μL/mL air (2.71 h) was significantly lower than LT50 obtained at exposure of bruchid to other lower doses of 0.78–3.15 μL/mL air.  相似文献   
19.
应用高效液相色谱 蒸发光散射检测法建立了测定草石蚕植物根茎中水苏糖含量的新方法 ,并设计和讨论了 2种从草石蚕根茎干粉中提取水苏糖的工艺方法。采用BondapakNH2 色谱柱 (3 0 0mm× 3 .9mmi.d .) ,流动相为甲醇 水 (80∶2 0 ,V V) ,流速 1 .0mL min,柱温为室温 ;蒸发光散射检测器漂移管温度 40℃ ,载气N2 流速 4.0L min。在上述条件下测得水苏糖在 1 .0 2~ 1 2 .2 2 μg范围内线性关系良好 (r=0 9995 ) ,检出限达到 0 .1 0 μg,平均加样回收率为 91 .6%。 2种不同提取方法的测定结果 :水苏糖含量分别为 2 9.8%和 2 5 .2 % ,纯度为 63 .76%和 88.3 5 %。该方法简便快捷 ,重现性和准确度良好 ,结果准确可靠 ,为实际样品的测定提供了科学依据。  相似文献   
20.
The chemical composition of the essential oil (EO) obtained from the aerial parts of Stachys benthamiana Boiss. was analysed by using GC and GC/MS. Thirty-three components were identified in the oil. β-Bisabolene (19.2%), humulene epoxide II (10.7%), epi-α-bisabolol (7.2%), (E)-γ-bisabolene (6.9%), n-decanal (6.8%) and caryophyllene oxide (6.6%), were the main compounds in the EOs. This is the first report on the different chemical compositions of S. benthamiana EOs from the south of Iran.  相似文献   
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