首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 578 毫秒
1.
Chloroform extract from the leaves of Turraea vogelii Hook f. ex Benth demonstrated cytotoxic activity against a chronic myelogenous leukemia cell, K-562 with IC50 of 14.27 μg/mL, while chloroform, ethyl acetate and methanol extracts from the stem of the plant inhibited K-562 cells growth with IC50 of 19.50, 24.10 and 85.40 μg/mL respectively. Bioactive chloroform extract of Turraea vogelii leaves affords two triterpenoids: oleana-12,15,20-trien-3β-ol (1), and oleana-11,13-dien-3β,16α,28-triol (2), with six fatty esters, ethyl hexaeicos-5-enoate (3), 3-hydroxy-1,2,3-propanetriyltris(tetadecanoate) (4), 1,2,3-propanetriyl(7Z,7′Z,7′′Z)tris(-7-hexadecenoate) (5), 1,2,3-propanetriyl(5Z,5′Z,5′′Z)tris(-5-hexadecenoate) (6), 1,2,3-propanetriyltris(octadecanoate) (7), and 2β-hydroxymethyl tetraeicosanoate (8). Tetradecane (9), four fatty acids: hexadecanoic acid (10), tetradecanoic acid (11), (Z)-9-eicosenoic acid (12), and ethyl tetradec-7-enoate (13) were isolated from chloroform extract of Turraea vogelii stem. 1,2,3-propanetriyltris(heptadecanoate) (14), (Z)-9-octadecenoic acid (15) and (Z)-7-tetradecenoic acid (16) were isolated from ethyl acetate extract while (Z)-5-pentadecenoic acid (17) was obtained from methanol extract of the plant stem. Compounds 1, 2, 5, 6, 11, 12, 15, 16 and 17 exhibited pronounced antiproliferative activity against K-562 cell lines.  相似文献   

2.
F. Noack  M. Notter  W. Weiss 《Liquid crystals》2013,40(6-7):907-925
Abstract

Systematic field-cycling measurements of the T 1 relaxation dispersion in numerous nematic liquid crystals (azoxybenzenes, Schiff's bases, biphenyls, phenyl-cyclohexanes, cyclo-cyclo-hexanes) confirm our previous observations obtained for PAA and MBBA that order fluctuations of the nematic director are a significant relaxation contribution only at low Lamor frequencies v, i.e. far below the usual megahertz range. Their significance is demonstrated most convincingly by the characteristic square-root dispersion law, T 1v 1/2, which occurs in the kilohertz range and which completely disappears above the nematic–isotropic phase transition. The strength of the collective relaxation mechanism varies by more than two orders of magnitude in the sequence (selection) PAA-d 8 PAA, PAA-d 6 PAB, OCB7, MBBA, CB7, PCH7, MBBA-d 6 MBBA-d 13 and CCH7. This finding can be understood almost quantitatively by the widely differing separations and orientations of proton pairs on the molecules, together with the different viscoelastic parameters of the nematogens. In addition, the underlying slow molecular reorientations have been observed in MBBA and PAA by intensity changes of the zero-field spectra, which are absent for high-field measurements. Similarly, smectic type order fluctuations in layered liquid crystal structures prove to be an effective relaxation mechanism only at low Lamor frequencies. This has been verified by the related linear relaxation dispersion profile, T 1v 1, for both thermotropic systems (TBBA, C12-AA) and lamellar lyotropic mixtures (e.g. potassium laurate in water and phospholipids in water). Our results concerning the time scale of the T 1v 1/2 and T 1 ~ v 1 regime do not agree with conclusions drawn from conventional high-field techniques.  相似文献   

3.
Thymelaea microphylla Coss. et Dur. (Thymelaeaceae) is a rare medicinal plant endemic to Algeria. In order to continue our studies on this species, herein we report the isolation and characterisation of 20 compounds from a hydroalcoholic extract (EtOH–H2O 7:3) of the aerial parts. They include monoterpene glucosides (13), phenolic acid derivatives (4, 8 and 9), phenylpropanoid glucosides (5 and 6), flavonoids (7, 10 and 11), a benzyl alcohol glucoside (12), ionol glucosides (1316), lignans (1719) and a bis-coumarin (20). All the structures were elucidated by spectroscopic methods including 1D and 2D NMR experiments, as well as ESI-MS analysis. Moreover, the extract of T. microphylla showed a significant and concentration-dependent free radical-scavenging activity in vitro, correlated to the presence of phenolic and chlorogenic acid derivatives (8, 9 and 4).  相似文献   

4.
Abstract

In the review article on cholesteric blue phases by Stegemeyer et al. [1], table 3 lists [100] as the second largest BPI facet and the largest BPII facet. If such is the case, then, it is important to realize that it is unlikely the body centred cubic phase of BPI has O8(I4 132) symmetry and the simple cubic phase of BPII, O2(P4232) symmetry [2–4].  相似文献   

5.
Phytochemical investigation of the ethanol extract from the whole plant of Agrimonia pilosa led to the isolation of 31 compounds, including 16 flavonoids (116), 5 triterpenes (1721), 1 isocoumarin (22), 5 phenolic acids (2327), 1 ceramide (28), 2 agrimols (2930) and 1 fatty acid (31). Their structures were determined by various spectroscopic analyses. Compounds 5, 7 and 20 were firstly isolated from the genus Agrimonia, and compounds 6, 1011, 15, 26, 28 and 31 were isolated from the family Rosaceae for the first time. Moreover, the chemotaxonomic significance of these compounds was summarised.  相似文献   

6.
The N,N-diphenylhydrazones1 and7 combine with oxalyl chloride yielding the corresponding 2,3-dihydropyrrole-2,3-diones (2), the indeno[1,2—b]pyrrol-2,3-dion derivative8 a and the 1-diphenylamino-4,5-tetrahydrobenz[g]indol-2,3-dione (8 b).2 can be rearranged into the pyrrolo[2,3—b]indole systems3 by thermolysis in decaline. Heating of3 a gives ethyl 1,2-diphenyl-indole-3-carboxylate5, while3 b under the same conditions is converted into the (indolyl-)glyoxylic acid derivative4. The diaza-propellanes9 are synthesized by thermolysis of8 in decaline. Oxidative hydrolysis of9 leads to the indole derivatives10, which on the other hand are made byFischer indole synthesis starting with7.  相似文献   

7.
With ethyl isothiocyanate, the stereoisomericcis- andtrans-2-hydroxymethyl-1-cyclohexylamines and theirN-methyl andN-benzyl derivatives (4 a–c,5 a–c) furnished the corresponding thiocarbamates (6 a–c,7 a–c). Treatment of compounds6 and7 with methyl iodide and subsequent alkali treatment afforded 3,1-perhydrobenzoxazines8 a–c,9 a–c, while cyclization of compounds6 and7 to the 3,1-perhydrobenzothiazines10 a–c,11 a–c was performed with HCl. It was found that the predominant conformation of theN-unsubstitutedcis isomers8 a and10 a is theN-inside form, while theN-substituted derivatives8 b,c and10 b,c have theN-outside preferred conformation.
Stereochemische Untersuchungen, 98. Gesättigte Heterocyclen, 100. Synthese von stereoisomeren 2-Ethylimino-3,1-perhydrobenzoxazinen und benzothiazinen
Zusammenfassung Aus den stereoisomerencis- undtrans-2-Hydroxymethyl-1-cyclohexylaminen und ihrenN-Methyl- undN-Benzylderivaten (4 a–c,5 a–c) wurden mit Ethylisothiocyanat die entsprechenden Thiocarbamate (6 a–c,7 a–c) erhalten. Behandlung der Verbindungen6 und7 mit Methyljodid und anschließend Alkali ergab die 3,1-Perhydrobenzoxazine8 a–c,9 a–c, während mit HCl die Cyclisierung zu den 3,1-Perhydrobenzothiazinen10 a–c,11 a–c eintrat. Es wurde festgestellt, daß die bevorzugte Konformation derN-unsubstituiertencis-Isomeren8 a und10 a die N-innen-Form ist, während die derN-substituierten Derivate8 b,c und10 b,c bevorzugt in der N-außen-Form vorliegen.
  相似文献   

8.
Six Diels–Alder adducts (16) and nine prenylated flavanones (715) were isolated from the root bark of Morus alba L. Among them, soroceal B (1) and sanggenol Q (7) were new compounds. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D and 2D NMR techniques. Compounds 13, 9, 10, 12, 13 and 15 exhibited cytotoxic activity against five human tumour lines and compound 2 inhibited significantly selective cytotoxic activities towards HL-60 and AGS cells with IC50 of 3.4 and 3.6 μM. Compounds 3, 5, 9 and 12 exhibited moderate inhibitory activity against nitric oxide production in LPS-activated RAW264.7.  相似文献   

9.
Summary The treatment of 2-(oxo-1-azetidinyl)-benzyltriphenylphosphponium salts9 and13b,c,d, ande with base leads to carbacephemes10 and14b,c,d, ande which can be reduced to the title compounds. The reaction of14 with acids does not result in 3-oxocephames by cleavage of the enolether function. Instead, the 3-alkoxyquinolines15b andc have been obtained.
  相似文献   

10.
Zusammenfassung 4-Benzoyl-5-phenyl-2,3-dihydro-furan-2,3-dion (1) setzt sich mit Arylisocyanaten unter CO-Abspaltung zu den Oxazin-2,4-dionen3 bzw.4 um.1 und p-Tolylcarbodiimid reagieren hingegen zum 4-Hydroxy-chinolin9 weiter. Die 4-Hydroxy-chinoline9 bzw.17 erhält man unabhängig davon durch thermische Belastung der Pyrrol-2,3-dion-Derivate14 bzw.15, die aus den entsprechenden Dibenzoylmethananilen und Oxalylchlorid synthetisierbar sind. Als Zwischenstufen dieser Cyclisierungsreaktionen werden -Acylheterocumulene (2 bzw.12,19) postuliert.
Reactions of cyclic oxalyl compounds, VI: Syntheses of heterocycles, CLXI
4-Benzoyl-5-phenyl-2.3-dihydro-furan-2.3-dione (1) reacts with aryl isocyanates with loss of CO to give the oxazine-2.4-diones3,4, resp. However, the reaction between1 and p-tolylcarbodiimide goes further, yielding the 4-hydroxyquinoline9. The quinolines9 and17 are obtained by an independent route by heating the pyrrole-2.3-diones14 and15, which can be synthesized from dibenzoylmethane aniles and oxalyl chloride. -Acylheterocumulenes (2,12,19, resp.) are postulated as intermediates for these cyclization reactions.


Herrn Univ.-Prof. Dr.H. Nowotny, Vorstand des Inst. f. Physik. Chemie der Universität Wien, gewidmet.  相似文献   

11.
Abstract

A new sesquiterpene lactone geigerianoloide (1) and four known flavonoids axillarin (2), quercetin (3), 3-methoxy-5,7,3',4'-tetrahydroxy-flavone (4) and hispidulin (5) were isolated from Geigeria alata (DC) Oliv. & Hiern. (Asteraceae). Structures were deduced using 1H- and 13C- NMR spectroscopy, mass spectrometry, while the structure of compound 1 was also deduced using X-ray crystallography technique.

Geigeria alata is traditionally used for diabetes, therefore compounds were tested for anti-glycation activity, in which compounds 2 and 3 showed potent activities (IC50 values of 246.97?±?0.83 and 262.37?±?0.22 µM, respectively) compared to IC50 value 294.50?±?1.5 µM of rutin. Moreover, compound 4 exhibited a comparable activity to rutin (IC50?=?293.28?±?1.34 µM). Compound 5 showed a weak activity.

Compounds 2, 3, and 4 exhibited potent DPPH radical scavenging activity (IC50?=?0.1?±?0.00, 0.13?±?0.00 and 0.15?±?0.01 µM, respectively). Compounds 2, 3, and 4 demonstrated significant superoxide anion scavenging activity with IC50 values of 0.14?±?0.001, 0.17?±?0.00, and 0.11?±?0.006 µM, respectively.  相似文献   

12.
We have developed a new method to simultaneously determine five marker compounds in Menthae Herba via HPLC/PDA – including hesperidin (1), rosmarinic acid (2), diosmin (3), didymin (4) and buddleoside (5). The newly developed method was successfully used to analyse for two species (Mentha arvensis L. and Mentha haplocalyx Briq.) of Menthae Herba, and the satisfactory results were obtained from the validation of developed method. The pattern analysis could greatly discriminate between M. arvensis L. and M. haplocalyx Briq. In conclusion, the proposed HPLC/PDA method is suitable for quality evaluation of Menthae Herba.  相似文献   

13.
Three new compounds (13) and seven known compounds (410) have been isolated from the ethanolic extract of Viburnum macrocephalum f. keteleeri using bioactivity-guided fractionation and identified as methyl (2-α-L-rhamnopyranosyloxy)acetate (1), methyl (2R-3-α-L-rhamnopyranosyloxy)glycerate (2), methyl (3R-4-α-L-rhamnopyranosyloxy-3-hydroxy)butanoate (3), bridelionoside B (4), (6S,7E,9R)-roseoside (5), linarionoside A (6), 3,7,11-trimethyl-1,6-dodecadien-3,10,11-triol (7), (+)-8-hydroxylinalool (8), β-sitosterol (9) and daucosterol (10). The structures of 13, including absolute configurations, were determined by spectroscopic data (1H and 13C NMR, HSQC, HMBC and ORD) and chemical methods. In addition, compounds 1–8 were assayed for their insecticidal and antimicrobial activities. Compounds 7 and 8 exhibited moderately insecticidal effects against Mythimna separata with LD50 values of 180 and 230 μg g?1, respectively. Compounds 2, 3, 7 and 8 showed varying antimicrobial activities with IC50 values ranging from 125 to 529 μM.  相似文献   

14.
The reactions of dipotassium and disodium salts of the tetraphenylethylene dianion with LuCl3(THF)3 or CpLuCl2(THF)3 yielded the homoleptic ate-complexes [Na(THF)5][Lu(Ph2CCPh2)2] (1) and [K(THF)5][Lu(Ph2CCPh2)2] (2) or the heteroleptic complex CpLu(Ph2CCPh2)(THF)2 (4), respectively. Recrystallization of complex 1 from a diglyme—THF mixture afforded [Na(diglyme)2][Lu(Ph2CCPh2)2](THF)0,5 (3). Recrystallization of complex 4 from 1,2-dimethoxyethane gave [CpLu(Ph2CCPh2)(DME)](DME) (5). The structures of complexes 3 and 5 were established by X-ray diffraction analysis. In both complexes, the unusual η6-coordination of the (Ph2CCPh2)2− dianion to lutetium is observed. The Lu-C distances vary from 2.441(2) to 2.643(2) Å (3) and from 2.470(3) to 2.763(3) Å (5). In complexes 3 and 5, a redistribution of the C-C bond lengths was observed in the Ph groups coordinated to lutetium. Studies by 1H, 13C, and 2D NMR spectroscopy demonstrated that the η6-coordination of the tetraphenylethylene dianion in homoleptic ate-complexes 1 and 2 is retained in a THF solution, whereas the coordination of this dianion in heteroleptic complex 4 changes from η6 to η4.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2060–2068, October, 2004.  相似文献   

15.
Zusammenfassung Methoxycymantren (3) wurde aus Cymantren-diazoniumsulfat über das sehr oxydationsempfindliche Hydroxycymantren hergestellt. Das ebenfalls zur Oxydation neigende Mercaptocymantren (7) läßt sich bei O2-Ausschluß nach Reduktion des Sulfochlorides5 isolieren.7 ergibt mit Dimethylsulfat Methylthiocymantren (9) und mit Chloressigsäure S-Cymantrenyl-thioglykolsäure (12). Aus12 ist durchFriedel-Crafts-Cyclisierung das Keton14 und daraus Thienocymantren (16) zugänglich. 3 und—in geringerm Maße-9 erwiesen sich bei derFriedel-Crafts-Acetylierung als -dirigierend. Die Acetylierung von Thienocymantren (16) ergibt ein Mono- und zwei Diacetylderivate. Die Strukturen wurden aus den NMR-Spektren und MS abgeleitet.
Electrophilic substitution of cymantrenes, III: Methoxy-, mercapto-, and thieno-cymantrenes (cymantrene derivatives, X)
Methoxycymantrene (3) was prepared from cymantrene diazonium sulfate via (the very oxygen sensitive) hydroxycymantrene. Mercaptocymantrene (7), which is also prone to autoxidation, can be isolated, if O2 is excluded, after reduction of the sulfonyl chloride5. 7 yields with dimethyl sulfate methylthiocymantrene (9). The reaction with chloroacetic acid produces S-cymantrenyl thioglycolic acid (12). From12 the ketone14 and thence thienocymantrene (16) is accessible by cyclisation.


2. Mitt.:H. Egger undA. Nikiforov, Mh. Chem.99, 2311 (1968).

9. Mitt.:H. Egger undA. Nikiforov, Mh. Chem.100, 483 (1969).  相似文献   

16.
Reaction of the vicinal diols of steroids1, 5, 7, 10, 13, and16 with TPP/DEAD yields both regio-and stereospecifically the oxosteroids2, 6, 8, 11, 14, and15 by displacement of an axial hydrogen and extrusion ofTPPO besides the cholest-4-en-6-ols9 and12 and the cyclic carbonate3. 16, 17-androstandiol16 gives only the cyclic carbonate17. The different structures of the carbohydrates withcis-diol arrangement19 and21 lead exclusively to cyclic carbonates20 and22 in moderate yields. Treatment of1 with TPP/DEAD/HN3 affords 3-azido-2-hydroxycholestane4 in addition to the above mentioned2.
  相似文献   

17.
A new aromatic glucoside, namely 4-methoxyphenyl-(6-deoxy-α-L-mannopyranosyl)-β-D-glucopyranoside (1), together with six known aromatic glucosides (27) were isolated from the stem bark of Illicium difengpi. The structures of these compounds were established by spectroscopic methods. The isolated aromatic glucosides were tested for anti-inflammatory activity. Compounds 1, 3 and 6 showed significant inhibitory effect on nuclear factor kappa B (NF-κB) in RAW 264.7 macrophages induced by lipopolysaccharide.  相似文献   

18.
Summary The preparation of the pyridazinones10a,10b,11a,11b, and12a,12b from the ketoamides7,8, and9 and hydrazine hydrate is described. It was found that from ketoamides8b and9b in addition to the expected pyridopyridazinones11b and12b also aminopyridopyridazines14 and15 were formed and that ketoamide7b gave exclusively aminopyridopyridazine13. The pyridopyridazinones10b,11b, and12b were alkylated with alkyl iodides.
Anwendungen von Organolithium und verwandten Reagenzien in organischen Synthesen, Teil XII. Synthese von Phenyl- und Pyridylpyridopyridazinonen und ihren Derivaten
Zusammenfassung Die Darstellung der Pyridazinone10a,10b,11a,11b und12a,12b aus Ketoamiden7,8 und9 und Hydrazinhydrat wird beschrieben. Es wurde festgestellt, daß aus Ketoamiden8b und9b außer den erwarteten Pyridopyridazinonen11b und12b auch Aminopyridopyridazine14 und15 enstanden und daß das Ketoamid7b ausschließlich ins Aminopyridopyridazin13 überführt wurde. Die Pyridopyridazinone10b,11b und12b wurden mit Alkyljodiden alkyliert.
  相似文献   

19.
Abstract

Phytochemical composition of ethyl acetate fraction and total phenolic content, in vitro antioxidant, anti-inflammatory, antimicrobial activities of petroleum ether, chloroform, ethyl acetate and n-butanol fractions of the ethanol extract obtained from the subaerial parts of Scorzonera pygmaea Sibth. & Sm. (Asteraceae) were investigated. Nine compounds; scorzopygmaecoside (1), scorzonerol (2), cudrabibenzyl A (3), thunberginol C (4), scorzocreticoside I (5) and II (6), chlorogenic acid (7), chlorogenic acid methyl ester (8), 3,5-di-O-caffeoylquinic acid (9) were isolated and identified using spectroscopic methods. All substances were isolated for the first time from this species. Compounds 1 and 2 are new. The fractions showed high antioxidant capacity correlated with their phenolic content and no significant antimicrobial activity against tested bacteria and fungi. COX inhibition test was used to evaluate the anti-inflammatory activity and all the fractions showed low inhibition in comparison with indomethacin.  相似文献   

20.
Summary The direct intramolecular acylation and alkylation of the phenylsulfonylmethyl-group in the -lactames5a and7 are not successful. The postulated intermediate8 of the acylating reaction could be quenched with trimethylchlorosilane as the stable silylketale10. Desulfonation and desilylation of10 leads to the title compound12. The reaction of7 with base does not result in a carbacephame. Instead, the benzo[b]-azepinones15c,d have been obtained.
  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号