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1.
海南栽培肾茶的化学成分研究 总被引:1,自引:0,他引:1
为了解肾茶(Clerodendranthus spicatus)的化学成分,从海南栽培肾茶地上部分分离得到11个化合物,经波谱分析分别鉴定为:吐叶醇(1)、丁香脂素(2)、3,4-二羟基苯乙醇(3)、甜橙素(4)、5,6,7,4′-四甲氧基黄酮(5)、5-羟基-6,7,3′,4′-四甲氧基黄酮(6)、6-羟基-5,7,4′-三甲氧基黄酮(7)、5-羟基-6,7,3′,4′-四甲氧基黄烷酮(8)、3,3′,5-三羟基-4′,7-二甲氧基-二氢黄酮(9)、松脂素(10)和熊果酸(11)。化合物3、9和10为首次从肾茶中分离得到。对化合物1~6进行活性测试,结果表明化合物3~5对乙酰胆碱酯酶具有一定的抑制活性。 相似文献
2.
为了解人工诱导海南龙血树(Dracaena cambodiana)所产血竭的化学成分,从其乙醇提取物中分离得到10个化合物,经波谱分析分别鉴定为socotrin-4?-ol(1)、homoisosocotrin-4?-ol(2)、(E)-3-(3,4-dihydroxybenzylidene)-7-hydroxy-chroman-4-one(3)、5-hydroxy-7-methoxy-3-(4?-hydroxybenzyl)-4-chromanone (4)、3-去氧苏木查耳酮(5)、苏木查耳酮(6)、7,4?-二羟基黄酮(7)、7,4?-二羟基-8-甲基黄酮(8)、丁香树脂醇(9)和邻苯二甲酸二(2-乙基己基)酯(10)。化合物1~10均为首次从人工诱导海南龙血树所产血竭中分离得到,其中化合物8为新天然产物,化合物3~6为首次从血竭中分离得到。化合物7和8对耐甲氧西林金黄色葡萄球菌具有生长抑制作用。 相似文献
3.
Density functional theory has been used to study copper(I)-catalysed aziridination of diazoacetate with imines. All the intermediates and the transition states were optimised completely at B3LYP/6-31G(d) level. Calculation results confirm that copper(I)-catalysed aziridination of diazoacetate with imines is exothermic, and the total released Gibbs free energy is about ? 170 kJ/mol. Copper(I)-catalysed aziridination has two reaction modes: I and II, and thus the reaction mode I is dominant. The formation of the copper(I)–carbene–imine complex M3 (i.e. the attack of imines on copper–carbon(carbene) of copper–carbene intermediate M2) is the rate-determining step and the chirality-limiting step for copper-catalysed asymmetric aziridination. The reaction channel CA2 → M1a → TS1a → M2 → TS2a2 → M3a2 → TS3a2 → M4a2 → P1 is the most favourable one. The dominant products predicted theoretically are of (R)-chirality. 相似文献
4.
Ken-ichi Takatsuki Sumito Ohgushi Shigeo Kohmoto Keiki Kishikawa Makoto Yamamoto 《Nucleosides, nucleotides & nucleic acids》2013,32(7):719-734
Synthesis of antibiotics, puromycin and 3 ′-amino-3 ′-deoxy-N 6,N 6-dimethyladenosine 11 was achieved by utilizing the cyclic sulfite 6a of the xylo-3 ′,5 ′-dihydroxy group as a new protective group. The key synthetic step is the deprotection of the sulfite moiety through the intramolecular cyclization of 2-α-carbamate 7. In a similar manner, 2,2 ′-anhydro-pyrimidine nucleosides 15, ribo-cytidines 17 and 2 ′,3 ′-anhydroadenosine 14 were prepared in high yields from the corresponding sulfites 4, 5, and 6b, respectively. 相似文献
5.
为了解苦槛蓝(Myoporum bontioides)的化学成分,采用色谱分离法从叶中分离得到11个化合物,分别鉴定为:5,7,3’-三羟基-4’-甲氧基黄酮(1)、3,5,7,4’-四羟基-3’-甲氧基黄酮(2)、5,7,4’-三羟基-3’,5’-二甲氧基黄酮(3)、木犀草素(4)、山奈酚(5)、鼠李黄素(6)、5,7-二羟基二氢黄酮(7)、7,4’-二羟基二氢黄酮(8)、5,7,3’,4’-四羟基二氢黄酮(9)、5-O-乙酰基-3,7,3’,4’-四羟基二氢黄酮(10)和7-甲氧基香橙素(11)。除化合物4、7、11之外,其他化合物均为首次从苦槛蓝叶中分离得到。菌丝生长速率法测试表明化合物4、7~9和11对荔枝霜疫霉菌具有较好的抑菌活性。 相似文献
6.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):572-576
Some new structural type inhibitors of urease, i.e. 2,5-disubstituted-1,3,4-oxadiazoles (4a–e) and 4,5-disubstituted-1,2,4-triazole-3-thiones (5a–e) were synthesized in two steps from mandelic acid hydrazides (2a–e) and aryl isothiocyantes. The hydrazides in turn were synthesized from mandelic acid via esterification. Compounds 4a–e and 5a–e were evaluated against jack bean urease. Compounds 4d, 5b, and 5d were found to be more potent, with IC50 values of 16.1?±?0.12?µM, 18.9?±?0.188?µM, and 16.7?±?0.178?µM, respectively, when compared to the standard (thiourea; IC50?=?21.0?±?0.011?µM). These compounds may be subjected to further investigations for the development of antiulcer drugs. 相似文献
7.
Fatemeh Khosravi 《Journal of biomolecular structure & dynamics》2018,36(2):512-531
Four Co(III)-, Cu(II)-, Zn(II)-, and Pd(II)-based potent antibacterial complexes of formula K3[Co(ox)3].3H2O (I), [Cu(bpy)2Cl]Cl.5H2O (II), [Zn(bpy)3]Cl2 (III), and [Pd(bpy)2](NO3)2 (IV) (where ox is oxalate and bpy is 2,2′-bipyridine) were synthesized. They were characterized by elemental analyses, molar conductance measurements, UV–Vis, FTIR, 1H NMR, and 13C NMR spectra. These metal complexes were ordered in three combination series of I + II, I + II + III, and I + II + III + IV. Antibacterial activity was tested for each of these four metal complexes and their combinations against Gram-positive and Gram-negative bacteria. All compounds were more potent antibacterial agents against the Gram-negative than those of the Gram-positive bacteria. The four metal complexes showed antibacterial activity in the order I > II > III > IV and the activity of their combinations followed the order of I + II + III + IV > I + II + III > I + II. CT-DNA binding studies of complex I and its three combinations were carried out using UV–vis spectral titration, displacement of ethidium bromide (EB), and electrophoretic mobility assay. The results obtained from UV–vis studies indicated that all series interact effectively with CT-DNA. Fluorescence titration revealed that the complexes quench DNA-EB strongly through the static quenching procedures. The binding constant (Kb), the Stern–Volmer constant (Ksv), and the number of binding sites (n) were determined at different temperatures of 293, 300, and 310 K, respectively. The calculated thermodynamic parameters supported that hydrogen binding and Van der Waals forces play a major role in association of each series of metal complexes with CT-DNA and follow the above-binding affinity order for the series. 相似文献
8.
Hiroki Kumamoto Misato Fukano Shuhei Imoto Satoru Kohgo Yuki Odanaka Masayuki Amano 《Nucleosides, nucleotides & nucleic acids》2017,36(7):463-473
Synthesis of a novel 2′-deoxy-guanine carbocyclic nucleoside 4 constructed with spiro[2.4]heptane core structure in the aglycon moiety was carried out. Radical-mediated 5-exo-dig mode cyclization and following cyclopropanation proceeded efficiently to furnish the spiro alcohol 10. Subsequent Mitsunobu-type glycosylation between 13 and 14, deoxygenation of the 2′-hydroxyl group of 16 and deprotection of 17 gave the title compound 4. Compound 4 demonstrated moderate anti-HBV activity (EC50 value of 0.12 ± 0.02 µM) and no cytotoxicity against HepG2 cells was observed up to 100 µM. 相似文献
9.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):296-299
The bioassay-guided fractionation of H. oblongifolium has led to the isolation of potent urease inhibitors 1–3. The structures were elucidated by NMR and mass spectroscopic techniques. Compound 2 showed a potent enzyme inhibition activity (IC50 20.96?±?0.93), which is comparatively higher than that for the standard thiourea (IC50 21.01?±?0.51 μM). Compounds 1 and 3 also showed a significant activity, with IC50 37.95?±?1.93 and 138.43?±?1.23 μM, respectively. The sub crude fractions (F1, F2, F3, and F4) were tested in vitro for their urease inhibition activity. Fractions F2 and F4 showed significant activity with IC50 140.37?±?1.93 and 167.43?±?3.03 μM, respectively. 相似文献
10.
The rhodium-catalysed hydroacylation of alkene is one of the most useful C–H bond activation processes. The C–C bond-forming reactions via C–H bond activation have extensively been the focus of study in the fields of organic and organometallic chemistry. In this work, density functional theory has been used to study Rh(I)-catalysed hydroacylation and hydrogenation of ethene with formic acid. All the intermediates and the transition states were optimised completely at the B3LYP/6-311++G(d,p) level (LANL2DZ(d) for Rh, P). Calculation results confirm that Rh(I)-catalysed hydroacylation of ethene is exothermic and the released Gibbs free energy is ? 60.39 kJ/mol. Rh(I)-catalysed hydrogenation of ethene is also exothermic and the released Gibbs free energy is ? 150.97 kJ/mol. Rh(I)-catalysed hydroacylation of ethene is the dominant reaction mode for Rh(I)-catalysed hydroacylation and hydrogenation of ethene with formic acid. In Rh(I)-catalysed hydroacylation of ethene, the H-transfer reaction is prior to the C–C bond-forming reaction. Therefore, the reaction mode ‘a’ (i.e. ca → M1 → TS1 → M2 → TS2a → M3a → TS3a → M4 → P1) is the dominant reaction pathway for Rh(I)-catalysed hydroacylation and hydrogenation of ethene. The theoretically predicted dominant product is propane acid. 相似文献
11.
Ijaz Ahmad Itrat Fatima Nighat Afza Abdul Malik Muhammad Arif Lodhi Muhammad Iqbal Choudhary 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):918-921
Phytochemical investigations on the alkaloidal fraction of the whole plant of the Isatis tinctoria led to the isolation of the alkaloids 1-6., 3′-Hydroxyepiglucoisatisin (3), Epiglucoisatisin (2) were found to be potent urease inhibitors in a concentration-dependent manner with IC50 values 25.63 ± 0.74, 37.01 ± 0.41 and 31.72 ± 0.93, 47.33 ± 0.31 μM against Bacillus pasteurii & Jack bean urease, respectively. Compounds 3 and 2 also showed potent inhibitory potential against α-chymotrypsin with IC50 values of 23.40 ± 0.21 and 27.45 ± 0.23 μM, respectively. 相似文献
12.
Cheorun Jo Kyung Young Yoon Eun Jin Jang 《Bioscience, biotechnology, and biochemistry》2016,80(10):2022-2024
The xanthone glucoside mangiferin (1) was converted by γ-irradiation into three new compounds, mangiferdiol (2), mangiferinol (3), and isomangiferinol (4). The new compound 2 containing two hydroxymethyl groups instead of a ketone moiety exhibited significantly improved inhibitory activity against nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 value 47.1 ± 1.7 μM, compared to the mother mangiferin. 相似文献
13.
Mohammad Hossein Mehraban Salman Odooli Reza Yousefi Rasoul Roghanian Majid Motovali-Bashi Ali-Akbar Moosavi-Movahedi 《Journal of biomolecular structure & dynamics》2017,35(9):1968-1978
A vast research has been conducted to find suitable and safe carriers for vital and pH-sensitive drugs including antibiotics. This article reports the use of easily accessible and abundant purified beta-lactoglobulin (β-LG) protein as the potential carrier of widely used Kanamycin (Kana) and Ciprofloxacin (Cip) antibiotics. Spectroscopic techniques (Fluorescence, UV–vis, Circular Dichroism) combined with molecular docking were used to determine the binding mechanism of these drugs. Fluorescence studies showed moderate binding affinity with the calculated binding constants KCip = 60.1 (±0.2)?×?103 M?1 and Kkana = 2.5 (±0.6)?×?103 M?1 with the order of Cip > Kana. Results of UV–vis were consistent with fluorescence measurements and demonstrated a stronger complexation for Cip rather than Kana. The secondary structure of β-LG was preserved upon interaction with Kana; however, a reduction in β-sheet content from 39.1 to 31.9% was convoyed with an increase in α-helix from 12.8 to 20.5% due to complexation of Cip. Molecular docking studies demonstrated that preferred binding sites of these drugs are not the same and several amino acids are involved in stabilizing the interaction. Based on the achieved results, Kana and Cip can spontaneously bind to β-LG and this protein may serve as their transport vehicle. 相似文献
14.
Hina Siddiqui Muhammad Arslan Bashir Kulsoom Javaid Arsalan Nizamani Huma Bano Sammer Yousuf 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1392-1403
Tyramine derivatives 3–27 were synthesized by using conventional and environmental friendly ultrasonic techniques. These derivatives were then evaluated for the first time for their α-glucosidase (Sources: Saccharomyces cerevisiae and mammalian rat-intestinal acetone powder) inhibitory activity by using in vitro mechanism-based biochemical assays. Compounds 7, 14, 20, 21 and 26 were found to be more active (IC50?=?49.7?±?0.4, 318.8?±?3.7, 23.5?±?0.9, 302.0?±?7.3 and 230.7?±?4.0?μM, respectively) than the standard drug, acarbose (IC50?=?840.0?±?1.73?μM (observed) and 780?±?0.028?μM (reported)) against α-glucosidase obtained from Saccharomyces cerevisiae. Kinetic studies were carried out on the most active members of the series in order to determine their mode of inhibition and dissociation constants. Compounds 7, 20 and 26 were found to be the competitive inhibitors of α-glucosidase. These compounds were also screened for their protein antiglycation, and dipeptidyl peptidase-IV (DPP-IV) inhibitory activities. Only compounds 20, 22 and 27 showed weak antiglycation activity with IC50 values 505.27?±?5.95, 581.87?±?5.50 and 440.58?±?2.74?μM, respectively. All the compounds were found to be inactive against DDP-IV enzyme. Inhibition of α-glucosidase, DPP-IV enzymes and glycation of proteins are valid targets for the discovery of antidiabetic drugs. Cytotoxicity of compounds 3–27 was also evaluated by using mouse fibroblast 3T3 cell lines. All the compounds were found to be noncytotoxic. The current study describes the synthesis α-glucosidase inhibitory activity of derivatives, based on a natural product tyramine template. The compounds reported here may serve as the starting point for the design and development of novel α-glucosidase inhibitors as antidiabetic agents. 相似文献
15.
Zixin Xie Donghua Cheng Lu Luo Guoliang Shen Suwei Pan Yaqian Pan 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):905-919
A series of 4-bromo-N-(3,5-dimethoxyphenyl)benzamide derivatives were designed and synthesised as novel fibroblast growth factor receptor-1 (FGFR1) inhibitors. We found that one of the most promising compounds, C9, inhibited five non-small cell lung cancer (NSCLC) cell lines with FGFR1 amplification, including NCI-H520, NCI-H1581, NCI-H226, NCI-H460 and NCI-H1703. Moreover, the IC50 values for the compound C9 were 1.36?±?0.27?µM, 1.25?±?0. 23?µM, 2.31?±?0.41?µM, 2.14?±?0.36?µM and 1.85?±?0.32?µM, respectively. The compound C9 arrested the cell cycle at the G2 phase in NSCLC cell lines. The compound C9 also induced cellular apoptosis and inhibited the phosphorylation of FGFR1, PLCγ1 and ERK in a dose-dependent manner. In addition, molecular docking experiments showed that compound C9 binds to FGFR1 to form six hydrogen bonds. Taken together, our data suggested that the compound C9 represented a promising lead compound-targeting FGFR1. 相似文献
16.
目的:检测儿童的情绪能力,从而检验儿童情绪能力发展是否正常以及协助训练孤独症儿童的情绪能力。方法:设计了一套便携式的儿童情绪感知系统,检测儿童的情绪能力。本系统由心率信号采集模块,PC机端的软件以及情绪能力数据分析组成。结果:研制的儿童情绪能力感知系统具有便携、可穿戴等优点,能够准确地检测儿童情绪能力。结论:儿童情绪能力感知系统能够检测使用者的情绪能力,也能够在儿童情绪能力干预训练中记录孤独症儿童的情绪变化,为干预训练提供帮助。 相似文献
17.
《Nucleosides, nucleotides & nucleic acids》2013,32(10):709-721
ABSTRACT A series of novel acyclic nucleosides 10, 11, 21, and 22 were synthesized efficiently starting from D-lactose. The condensation of the mesylate 5 and 16 with an adenine and cytosine base under standard nucleophilic substitution conditions (K2CO3, 18-Crown-6, DMF) afforded a series of acyclic novel nucleosides. Compound 21 displayed moderate anti-HCMV activity in the AD-169 cells (EC50=18.5 µg/mL) without exhibiting any cytotoxicity up to 100 µM. 相似文献
18.
目的:探讨初始沙盘特征对患者社会功能缺陷的诊断评估作用。方法:选择292例心理门诊患者为研究对象,对其初始沙盘特征进行编码,使用社会功能缺陷量表评估其社会功能程度,使用差异检验探讨不同初始沙盘特征的患者社会功能之间的差异。结果:292例患者,在空白领域是否过大,沙盘是否存在分裂,是否存在无功能的桥、船等其他工具以及是否具有隔离空间的栅栏等维度上,社会功能缺陷差异显著(P0.05)。结论:患者的初始沙盘特征能够反映患者的社会功能缺陷程度。 相似文献
19.
Excessive uric acid production, which causes gout and hyperuricemia, can be blocked by inhibiting xanthine oxidase (XO). However, some agents to block on XO often cause side effects, thereby necessitating the identification of new inhibitors. During the screening of XO inhibitors from various mushroom extracts, we found that a methanolic extract of the fruiting bodies of Tyromyces fissilis, an inedible and non-toxic fungus, showed inhibitory activity. Both n-hexane and ethyl acetate layers, obtained by partitioning this extract exhibited XO inhibitory activity. Subsequently, using an activity-guided separation method, eight active compounds (1–8) were isolated. The structures of five of the new compounds, 2–4, 6, and 7, were elucidated by spectral analysis and chemical derivatization. All compounds had a salicylic acid moiety with an aliphatic group at the C-6 position. Notably, 2-hydroxy-6-pentadecylbenzoic acid (1) showed the highest level of XO noncompetitive inhibition (58.9 ± 2.2% at 25 µM). 相似文献
20.
《Journal of biological education》2012,46(1):83-87
Software Transpiration By J. M. Garland and U. Garland. Written for BBC Model B with colour monitor, cassette and disc versions. Produced by Garland Computing, 35 Dean Hill, Plymouth PL9 9AF. Price £10.00. Reviewd by W. G. Rogers Seed germination By J. M. Garland. Written for BBC Model B with colour monitor. Cassette and disc versions. Produced by Garland Computing, 35 Dean Hill, Plymouth, Devon PL9 9AF. Price £10.00 Reviewd by W. G. Rogers. Photosynthesis By J. M. Garland.Written for BBC Model B with colour monitor, cassette and disc versions. Produced by Garland Computing, 35 Dean Hill, Plymouth PL9 9AF. Price £10.00 Reviewed by W. G. Rogers. Slides/Strides Vertebrate reproduction Twenty-two.35 mm colour slides (including two title slides) with a study guide by David W. Macdonald. Ref. AV 218, price £16.80. Available from: Oxford Educational Resources Ltd, 197 Botley Road, Oxford 0X2 OHE Reviewed by Katrina Fuery Reproduction in mammals Twenty-two.35 mm colour slides (with two title slides) with teaching notes by David W. Macdonald, produced in association with Oxford Scientific Films Ltd and J. Dellar of Wildlife Consultants Ltd. Ref. AV 220, price £16.80. Available from Oxford Educational Resources Ltd, 197 Botley Road, Oxford OX2 OHE Reviewed by Claire Carpenter Mitosis and meiosis Two sets of 12 slides, each accompanied by a booklet containing background information and questions with answers. By Dr Judith Kinnear and Dr Marjory Martin. Refs M39825/8, M39820/9, price £9.95 each. Available from Philip Harris Biological Ltd, Oldmixon, Weston-super-Mare, Avon BS24 9BJ Cathy Maclean Marjorie Tindal Farm animal breeds Set of 24, colour, plastic-mounted slides supplied in a wallet with teaching notes by Dr Alan Beaumont. Available from Audio-Visual Productions Ltd, Hocker Hill House, Chepstow, Gwent NP6 5ER Ref. 977. Price £8.90 Adam Cade Basic techniques of plant tissue culture Twenty-six 35 mm colour slides in a plastic wallet with teaching notes. Ref M25080/2, price £16.25. Also available as a filmstrip, ref. M25084/9, price £11.00. Obtainable from Philip Harris Biological Ltd, Oldmixon, Westonsuper-Mare, Avon BS24 9BJ V. E. Stein Focus on bats Forty 35 mm plastic mounted colour slides and a 20 minute cassette soundtrack narrated by Dr R. Stebbings. Ref. A VP 080. Price £11 (or filmstrip £7) and tape £4 (inclusive of VAT and postage). Available from International Centre for Conservation Education, Greenfield House, Gutting Power, Cheltenham, Glos GL54 5TZ Kevin Walsh Introducing British reptiles Forty 35 mm colour slides, commentary booklet, and a leaflet on ‘Being kind to snakes‘ are supplied in a handy plastic wallet. Ref. AVP 075. Price £10.06 (includes VAT and postage). The commentary is also available on cassette. Also available as a film strip, price £5.00. Available from International Centre for Conservation Education, Greenfield House, Guiting Power, Cheltenham, Glos GL54 5TZ Iain Armstrong Introducing British amphibia Forty 35 mm colour slides, commentary booklet and a leaftlet on ‘Garden ponds as amphibian sanctuaries’. Ref AVP 074. Price £10.06 (includes VA T and postage). Also available as a film strip, price £5.00. An audio-cassette of the commentary will soon be available price £3.80. From International Centre for Conservation Education, Greenfield House, Guiting Power, Cheltenham, Glos GL54 5TZ Alison Muspratt Videotapes Investigating the nervous system A 20-minute video-cassette, ref. 84/031/ I, price £29.50. Also available as a 16 mm film price £395. Produced by Educational Media Australia, in association with the Australian Academy of Science, Schools Biology Project. Available from Educational Media International, 25 Boileau Road, London W5 3AL Jane O'Leary Reproduction in organisms A 16-minute video-cassette released in 1981, ref. 84J062JR, price £29.50. Also available as a 16 mm film price £205, ref. EM A AUS UP-S. Produced by Educational Media Australia. Available from Educational Media International, 25 Boileau Road, London W5 3AL Carol Burton Jenny Johnson Eat your heart out A videotape in two parts, lasting about an hour produced by Scope Films Ltd, and available from Concorde Films Council Ltd, 201 Felixstowe Road, Ipswich IP3 9BJ. Price: hire £10; sale £60 C. Thorpe P. Burdett Tapes Biorhythms: 1. Human biology; 2. General biology Each consists of a cassette tape and a 65+ page booklet. Words by Harold Baum, music by Peter Shade, sung by the ‘Metabolites’. Published by Learn Through Music Ltd. Distributed by: (UK) Taylor and Francis Ltd, 4 John Street, London WC1N 2ET; (USA) Taylor and Francis Inc., 242 Cherry Street, Philadelphia, PA 19106-1906. Each part £8.95 (1984). ISBNs 0 85066 291 5 and 0 85066 292 3 John A. Barker 相似文献