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41.
新疆圆柏化学成分研究 总被引:7,自引:0,他引:7
从新疆圆柏枝叶中分离得到9个化合物,经理化性质和光谱解析分别为扁柏双黄酮(hinokiflavone,1)、芹菜甙元(apigenin,2)、鬼臼毒素(podophyllotoxin,3)、苦松甙(coniferin,4)、肉豆蔻酸丙酯(propionic acetate myristic acid,5)、β-谷甾醇(β-sitosterol,6)、圆柏醇(sabinal,7)、反式璎珞酸(trans-communic acid,8)、蔗糖(sucrose,9),其中化合物1~4为首次从该植物中提取分离得到. 相似文献
42.
Yi Yang Dongyu Gu Abulimiti Yili Yongxin Zhao Dajun He Haji Akber Aisa 《Phytochemical analysis : PCA》2010,21(2):205-209
Introduction – Artemisia rupestris L. is a well‐known traditional Chinese medicinal plant in Xinjiang. Rupestonic acid is the main active ingredient of A. rupestris L., and has been chosen as a ‘marker compound’ for the chemical evaluation or quality control of A. rupestris L. and its products. Although HSCCC separation method was developed before, the separation was performed with two steps using the same solvent system, which were time‐consuming and waste of the solvents. Objective – To develop a simple HSCCC method for the separation and purification of rupestonic acid in a single run. Methodology – The measurement of partition coefficient (K) was introduced to select the two‐phase solvent system. The simple HSCCC method was established according to the selected solvent system for separation and purification of rupestonic acid. The purity of target compound was test by HPLC and the structure was identified by MS, 1H NMR and 13C NMR. Results – A total of 72.3 mg of rupestonic acid and 53.5 mg of chrysosptertin B with over 95% purity were yielded from 500 mg extracts of Artemisia rupestris L. in one‐step separation. Conclusion – The rupestonic acid was separated in a single run by HSCCC. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
43.
Fructus Euphorbia sororia is a widely used traditional medicine in China. Six new jatrophane-type diterpenoids (compounds 1–6) were isolated from Fructus E. sororia. The structures were elucidated by spectroscopic methods (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR). 相似文献
44.
E Aisa L Desideri P Guerrieri P Bonelli 《Bollettino della Società italiana di biologia sperimentale》1983,59(9):1383-1389
An investigation was carried out to identify the actual state of parasitism in the Scardinius erythrophthalmus L. population of Trasimeno lake (Umbria, Italy). Seasonal samples of fishes were taken in different points of the litoral and pelagic zones. The parasites found, together with the somatometric values and the characteristics of their localizations are reported. It has been found: a high number of infested specimens; eleven species of parasites, of which five were not yet known to be in the lake; frequency variations of certain species. The species of parasites observed are distributed in the Paleartic region. The five species, whose presence was not known in the lake, are considered to be allochtonous. The organs most frequently involved were, in descending order, the gills, the ureters, the gonads, the intestinal and mesenteric serous membranes, the liver. The most marked histologic alterations and reactions were observed as a consequence of Ergasilus sieboldi Nord. action and, in several cases, with the presence of Ligula intestinalis L. larvae. 相似文献
45.
The 1,2,3-triazole ring is a major pharmacophore system among nitrogen-containing heterocycles. These five-membered heterocyclic motifs with three nitrogen heteroatoms can be prepared easily using ‘click’ chemistry with copper- or ruthenium-catalysed azide-alkyne cycloaddition reactions. Recently, the ‘linker’ property of 1,2,3-triazoles was demonstrated, and a novel class of 1,2,3-triazole-containing hybrids and conjugates was synthesised and evaluated as lead compounds for diverse biological targets. These lead compounds have been demonstrated as anticancer, antimicrobial, anti-tubercular, antiviral, antidiabetic, antimalarial, anti-leishmanial, and neuroprotective agents. The present review summarises advances in lead compounds of 1,2,3-triazole-containing hybrids, conjugates, and their related heterocycles in medicinal chemistry published in 2018. This review will be useful to scientists in research fields of organic synthesis, medicinal chemistry, phytochemistry, and pharmacology. 相似文献
46.
Yang Y Gu D Aisa HA Ito Y 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(32):3802-3805
The performance of protein separation using the figure-8 column configuration in centrifugal counter-current chromatography was investigated under various flow rates and revolution speeds. The separation was performed with a two-phase solvent system composed of polyethylene glycol 1000/potassium phosphate each at 12.5% (w/w) in water and with lysozyme and myoglobin as test samples. In order to improve tracing of the elution curve, a hollow fiber membrane dialyzer was inserted at the inlet of the UV detector. The results showed that the retention of stationary phase (Sf) and resolution (Rs) increased with decreased flow rate and increased revolution speed. The highest Rs of approximately 1 was obtained at a flow rate of 0.01 mL/min under a revolution speed of 1200 rpm with a 3.4 mL capacity column. 相似文献
47.
48.
Aisa J Lahoz M Serrano P Pérez-Castejón MC Junquera C Martínez-Ciriano MC Pes N Vera-Gil A 《Histology and histopathology》2001,16(2):487-496
This is the first study which describes the innervation of some eyelid structures, such as the glands of Moll and the glands of Zeiss. It is also the first to investigate the innervation pattern of the eyelid as a whole. We have studied the acetylcholinesterase-positive and paraformaldehyde-induced-fluorescence-positive (FIF+) innervation pattern of the different structures that constitute the upper eyelid of the sheep. There is widespread acetylcholinesterase-positive innervation in the epithelium, but not such an abundant FIF+ innervation. Both types of innervation are represented in the connective tissue by trunks or fibers that are distributed towards the different structures immersed within them. In the glands of Zeiss, cholinesterase-positive innervation is much more widespread than FIF innervation. On the contrary, the glands of Moll present denser FIF+ innervation than acetylcholinesterase-positive innervation. The Meibomian glands and the lachrymal glands show a rich acetylcholinesterase-positive and FIF+ innervation. Eyelid muscle innervation is mainly acetylcholinesterase-positive. In the conjunctive membrane there is no acetylcholinesterase-positive innervation, and only scarce FIF+ fibers can be demonstrated. 相似文献
49.
Pérez-Castejón MC Vera-Gil A Lahoz M Aisa J Recreo MP Pes N Serrano P Barral MJ 《Histology and histopathology》2002,17(3):799-803
Following the works of Velazquez et al. (1999), Jo-Seung et al. (2000), Wang et al. (2001), Danscher et al. (2001) and the criteria of Zinc-containing neurons established by Frederickson et al.(2000), we have found the presence and localisation of Zinc in the neurons of the dorsal root ganglia of Wistar rat, by using Timm's thecnique and by studying the autoradiographic uptake of 65Zn. The agreement between the results of both techniques allows us to classify these spinal ganglion neurons as Zinc-containing neurons and also, to confirm some of the results of Velazquez et al. (1999). 相似文献
50.
Gen Li Jiang-Yu Zhao Chao Niu Li-Fei Nie Chang-Zhi Dong Haji Akber Aisa 《Bioorganic & medicinal chemistry letters》2017,27(6):1484-1487
A series of 1-(1′-hydroxyalkyl)rupestonic acid methyl esters were synthesized via the condensation of methyl rupestonate with various aldehydes in the presence of LDA. This mixed aldol reaction was highly stereoselective and all the new compounds were elucidated by detailed NMR and MS analyses. The absolute configurations of the newly formed stereocenters were further confirmed by X-ray crystallographic analysis of 3d, the results of which were found to be opposite to the prediction based on Zimmerman-Traxler’s and Houk’s models. All the compounds synthesized were then evaluated for their in vitro inhibitory activities against influenza A (H1N1 and H3N2) and B viruses. The data showed that 3p displayed the highest activity against influenza A H1N1 (IC50 = 0.69 μg/mL) and H3N2 (IC50 = 0.69 μg/mL) viruses, which were even better than Ribavirin and Oseltmivir. On the other hand, both 3c and 3o were found to show comparable activities with the reference drugs in inhibiting both influenza A and B viruses. Further studies will focus on reducing the cytotoxicity of the hits reported in this work. 相似文献