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1.
南丹参化学成分研究 总被引:4,自引:0,他引:4
从南丹参根中分得分得16个化合物,经光谱和理化分析测定,鉴定了其中的10个,分别为丹酚酸C(salvianolic acid C)、4-羟基-1-乙烯羧基-7-(3,4-二羟基苯基)苯并[b]呋喃(4-hydroxy-1-vinyl carboxy-7-(3,4-dihydroxyphenyl)benzo[b]furan)、丹参酮ⅡA(tanshinoneⅡA),丹参酮Ⅰ(tanshinoneⅠ)、二氢异丹参酮(dihydroisotanshinone)、7-羰基-12-羟基脱氯松香烷(7-carbonyl-12-hydroxy—dehydroabietane)、十八醇(octadecanol)、丹参内酯(tanshinlactone)、1,2-顺式-2-(3,4-二甲氧基-5-羟基苯基)-丙烯酸(1,2-cis-2-(3,4-dimethoxy-5-hydroxyphenyl)-acrylic acid、β-谷甾醇(β—sitosterol)。 相似文献
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金莲花药材经乙醇提取,聚酰胺、反相硅胶、凝胶柱色谱法分离得到4个苯乙素类化合物,根据理化性质和光谱数据分别鉴定为2-(3,4-二羟基-苯基)乙醇葡萄糖苷、2-(4-羟基,3-0-葡萄糖苯基)乙醇、2-苯基乙醇葡萄糖苷、2-(4-羟基苯基)乙醇葡萄糖苷。均为首次从该属植物中得到。 相似文献
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从紫茎泽兰(Eupatorium adenophorum Spreng.)乙醇提取物中分离得到11个酚类化合物。通过波谱分析,分别鉴定为咖啡酸(1)、阿魏酸(2)、芥子醛(3)、苯乙基阿魏酯(4)、3,4-二羟基苯甲酸(5)、4-羟基-3-甲氧基苯甲酸(6)、3,4-二甲氧基苯甲酸(7)、没食子酸(8)、3-(3,4-二羟基苯基)-1-丙醇(9)、2-香豆酸-β-D-吡喃葡萄糖苷(10)和4-O-β-D-葡萄糖苷-3,5-二甲氧基苯基-乙基酮(11)。化合物3~9和11为首次从紫茎泽兰中分离得到。 相似文献
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中药大蓟化学成分的研究 总被引:3,自引:0,他引:3
从大蓟的50%乙醇提取物中分离得到2个木脂素:(-)2-(3’-甲氧基4’-羟基-苯基)-3,4-二羟基4-(3"-4"-羟基-苄基)-3-四氢呋哺甲醇(1)和络石苷(2),以及另外6个化合物:蒙花苷(3)、柳穿鱼叶苷(4)、粗毛豚草素(5)、芹菜素(6)、咖啡酸(7)和对-香豆酸(8)。本文首次在蓟属植物中发现木脂素类成分,化合物7也为首次从本植物中分离得到,通过体外玻片法对化合物1—8进行凝血活性测定,发现化合物3、4具有一定的促凝血作用。 相似文献
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采用MTT法对从瓦宁木层孔菌子实体中分离得到的化合物樱花亭、7-甲氧基二氢莰非素、4-(3,4-二羟苯基)-3-丁烯-2-酮、二氢莰非素、hispolon进行了体外抗肿瘤活性研究。试验结果表明:当质量浓度为100μg/mL时,化合物4-(3,4-二羟苯基)-3-丁烯-2-酮和hispolon对人肝癌细胞SMMC-772... 相似文献
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为了解姜黄(Curcuma longa L.)地上部分的化学成分,采用硅胶、葡聚糖凝胶柱色谱和高效液相色谱从姜黄地上部分分离得到14个化合物。通过波谱分析,分别鉴定为槲皮素3-O-α-L-鼠李糖苷(1)、山柰酚3-O-α-L-鼠李糖(1→2)-α-L-鼠李糖苷(2)、橙皮素7-O-α-L-鼠李糖(1→6)-β-D-葡萄糖苷(3)、1,7-二(4-羟基苯基)庚烷-4E,6E-二烯-3-酮(4)、1,7-二(4-羟基苯基)庚烷-1E,4E,6E-三烯-3-酮(5)、3-羟基-4-甲氧基肉桂酸(6)、对羟基苯甲醛(7)、香草醛(8)、4-羟基-3-甲氧基苯甲酸(9)、异香草酸(10)、4-(1-羟基-1-甲基乙基)苯甲酸(11)、R-6-羟基-6-甲基-3-(2-羟基异丙基)-2-烯环己酮(12)、6,9-二羟基-4,7-巨豆二烯-3-酮(13)和β-胡萝卜苷(14)。化合物1、2、3、12和13首次从该植物中分离得到。经HPLC比较分析,姜黄地上部分缺乏姜黄药材的主要功能成分姜黄素。 相似文献
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The bioassay was directed to the fractionation of the methanol extract of the rhizomes of Zingiber officinale Roscoe leading to the isolation of a new antioxidant cyclic diarylheptanoid. The structure of the new compoundwas established as 1,5-epoxy-3-hydroxy-1-(3,4-dihydroxy-5-methoxy-phenyl)-7-(3,4-dihydroxy-phenyl) heptane (1) on the basis of MS, 1D and 2D-NMR experiments. 相似文献
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The wood of Virola multinervia Ducke (Myristicaceae) contains sitosterol, stigmasterol and two novel diarylpropanoids virolane [1-(2-hydroxy-4-methoxyphenyl)-3-(3,4-methylenedioxyphenyl)-propane] and virolanol [2-hydroxy-1-(2-hydroxy-4-methoxyphenyl)-3-(3,4-methylenedioxyphenyl)-propane]. 相似文献
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1. Using single chloroplasts of Peperomia metallica the kinetics of light-induced potential changes were studied. Three kinetic components (the initial fast rise, the decay in the light and the decay in the dark) were found to be characterized by time constants 4, 220 and 60 ms, respectively at light intensity 5000 lx and temperature 18 °C. After flash excitation the potential kept on rising for about 10 ms. Cooling of the medium down to 5 °C had no effect on the duration of potential rise after the flash.2. Variations in the medium temperature in the range 2–23 °C had little effect on photoresponse magnitude but resulted in significant acceleration of decay in the light.3. Addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (5 · 10?6 M) resulted in suppression of the magnitude of the photoresponse but was not accompanied by any change in the rate of initial rise of potential. 3-(3,4-Dichlorophenyl)-1,1-dimethylurea-inhibited photoresponse could be restored and even enhanced by subsequent addition of N-methylphenazonium methosulfate (10?4 M). N-Methylphenazonium methosulfate essentially influenced the time course and light-intensity curves of photoresponse.4. The chloroplast photoresponses were of different time-courses when elicited by red (640 nm) or far red (712 nm) light. This fact as well as an enhancement effect of combined illumination by two intermittent light beams indicate on the interaction of two photosynthetic pigment systems when the photoelectric response was formed.5. An imposed electrical field resulted in stimulation or suppression of chloroplast photoresponse depending on the polarity of the field. No indications for the existance of “reversal potential” for photoelectric response were obtained.6. A kinetic scheme of photoresponse formation is proposed, which includes two sequential photochemical reactions of photosynthesis. 相似文献
14.
Siegfried Huneck Joseph D. Connolly Leslie J. Harrison Robert S.I. Joseph Thomas Pócs 《Phytochemistry》1984,23(10):2396-2397
Extraction of the liverwort Plagiochila rutilans afforded 1-(3,4-dihydroxy-5-methoxyphenyl)3-methylbut-2-ene, the structure of which was confirmed by synthesis. 相似文献
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The pH of the suspension medium was found to have a remarkable influence on the “slow” (min) time course of Chlorophyll a fluorescence yield in the green alga Chlorella pyrenoidosa and in the blue-green alga Anacystis nidulans. In Chlorella, the decay of fluorescence yield, in the 1- to 5-min region, is strongly retarded at alkaline pH; this decay rate shows an optimum at pH 6–7. In Anacystis, the rise of fluorescence yield, in the same time range, is decreased optimally at pH 6–7; poisoning with 3(3,4-dichlorophenyl)-1,1-dimethylurea reverses the direction of this pH effect. These observations suggest a correlation of the H+ status (or the processes associated with it such as photophosphorylation and resulting conformational changes) of the chloroplast to the yield of chlorophyll a fluorescence in vivo. 相似文献
16.
Simultaneous measurements of hydroxylamine photo-oxidation and fluorescence induction were performed in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). The results provide a justification for the common use of fluorescence data to estimate the concentration of active System II centers in the presence of inhibitors.The addition of DCMU to dark-adapted chloroplasts under special conditions induces a large increase of the initial yield of fluorescence. A reversible inactivation of part of the System II centers is responsible for this effect. Similar data were obtained with other classical inhibitors of oxygen evolution. 相似文献
17.
Abhishek Chowdhury Shantanu Sen Pradip Dey Pankaj Chetia Anupam Das Talukdar Amitabha Bhattacharjee Manabendra Dutta Choudhury 《Bioinformation》2012,8(18):875-880
The advent of Multi Drug Resistant (MDR) strain of Mycobacterium tuberculosis (TB) necessitated search for new drug targets for the
bacterium. It is reported that 3.3% of all new tuberculosis cases had multidrug resistance (MDR-TB) in 2009 and each year, about
0.44 million MDR-TB cases are estimated to emerge and 0.15 million people with MDR-TB die. Keeping such an alarming situation
under consideration we wanted to design suitable anti tubercular molecules for new target using computational tools. In the work
Methionine aminopeptidase (MetAP) of Mycobacterium tuberculosis was considered as target and three non-toxic phenolic=ketonic
compounds were considered as ligands. Docking was done with Flex X and AutoDock 4.2 separately. Ten proven inhibitors of
MetAP were collected from literature with their IC50 and were correlated using EasyQSAR to generate QSAR model. Activity of
ligands in question was predicted from QSAR. Pharmacophore for each docking was generated using Ligandscout 3.0. Toxicity of
the ligands in question was predicted on Mobyle@rpbs portal and Actelion property explorer. Molecular docking with target
showed that of all three ligands, 3-ammonio-3-(4-oxido-1H-imidazol-1-ium-5-yl) propane-1, 1-bis (olate) has highest affinity (-
37.5096) and lowest IC50 (4.46 µM). We therefore, propose that -3-ammonio-3-(4-oxido-1H-imidazol-1-ium-5-yl) propane-1,1-
bis(olate) as a potent MetAP inhibitor may be a new anti-tubercular drug particularly in the context of Multi Drug Resistant
Tuberculosis (MDR-TB). 相似文献
18.
Photodesmosine,an isomer of desmosine obtained by photolysis of this amino acid in ultraviolet light
Jean-Francois Larochelle Francois Lamy 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,584(2):327-338
Desmosine and isodesmosine are two isomers representing the main cross-links of elastin. We describe a new isomer, photodesmosine, which is produced by the photolysis of desmosine at 254 nm. The mechanism of this photolysis is described and is shown to consist of two competing paths. After opening of the pyridium ring to give a tetrasubstituted aminoketone, this compound can either be hydrolysed to give lysine and a trisubstituted analogue of glutaconic aldehyde or undergo a recyclisation and rearomatisation to give a pyridium compound substituted in positions 1, 2, 3 and 4. An understanding of this mechanism is important in order to use photolysis as a specific method to break elastin cross-links. Although only desmosine and isodesmosine have been reported in purified elastin, the chromatographic properties of photodesmosine suggests that if other natural isomers exist in this protein they could be eluted from an ion-exchange resin at much earlier times than those observed in the case of the two already described cross-links. 相似文献
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A cell-free preparation has been isolated from a mutant of Cyanidium caldarium, grown under conditions such that there is 15 times less chlorophyll per photosynthetic unit than in normal green algae. The preparation is sensitive to 3-(3,4-dichlorophenyl)-1,1-dimethylurea and shows the well-characterized oscillation of O2 yield, from saturating flashes, following a period of dark adaptation. Greening experiments with dark-grown, wild-type Cyanidium show that the synthesis of photosynthetic units precedes that of bulk chlorophyll and that the O2-producing system is assembled before the total system coupled to CO2. No large-scale cooperation of chlorophyll molecules is required for O2 production. 相似文献