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1.
Microwave-assisted conjugate addition of indole on nitro-olefins furnished nitro compounds, which were reduced to tryptamines. Further, by using Pictet-Spengler condensation, new 1,4-disubstituted-1,2,3,4-tetrahydro-β-carbolines were synthesized in diastereoselective manner. Dehydrogenation of the tetrahydro-β-carbolines produced new 1,4-disubstituted-β-carbolines. As a new observation, in some of the cases, Pictet-Spengler condensation and dehydrogenation gave two products, namely 1,4-disubstituted-β-carbolines and 1,4-disubstituted-γ-carbolines. A mechanism is proposed for this observation. 相似文献
2.
H. Tsuchiya M. Sato H. Hayashi H. Kato H. Kureshiro T. Hayashi 《Chromatographia》1996,43(7-8):419-425
Summary Reversed-phase ion-pair HPLC with fluorimetric detectors connected in series was studied for the simultaneous determination of two tetrahydro--carbolines and two -carbolines. After additon of internal standards the samples were reacted with fluorescamine, and then subjected to serial extractions to remove their precursor (tryptamine) from the analytical system. This treatment not only suppressed the artefactual formation of tetrahydro--carbolines and -carbolines during analysis, but also effectively purified them. Under optimum conditions, using trifluoroacetic acid as counter ion, all analytes were separated within 14 min and without major interfering peaks. The quantitative ranges were 0.25–80.0 ng mL–1 for both tetrahydro--carbolines and 0.1–30.0 ng mL–1 for both -carbolines. Replicate spiking experiments showed that recovery from most of the samples tested was over 90% and the relative standard deviation ranged from 0.7 to 10.4% within and between assays. The proposed method was applicable to various materials such as soy sauce, vinegar, ketchup, tabasco, beer, wine, sake, whisky, brandy, cows' milk, coffee, cocoa, cheese, cigarette smoke and urine. 相似文献
3.
Elizabeth Malamidou-Xenikaki Christina Vlachou Xenophon N. Stampelos 《Tetrahedron》2006,62(42):9931-9941
2-[1-(ω-Nitroalkyl)-1H-indol-3-yl]ethylformamides 11 were transformed to the corresponding 9-(ω-nitroalkyl)-4,9-dihydro-3H-β-carbolines 5 and through a diastereoselective intramolecular aminoalkylation to the annulated tetrahydro-β-carbolines 13, in high yields. Intramolecular N-acyliminium cyclisation of compounds 5 afforded the tetracyclic diazacycloalkano[jk]fluorenes in two diastereoisomeric forms 18 and 19 with moderate selectivity. Conjugate addition reactions performed on compounds 18 and 19 led to pentacyclic indolo[3,2,1-de]pyrido[3,2,1-jk]naphthyridinone 26a or diazabenzo[a]naphtho[2,1,8-cde]azulenone 26b. 相似文献
4.
Yu-Gui Li Yun-Shan Liu Fang-Ming Miao Xiao-Lan Liu Jin-Hong Cao Wei Zhou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):57-60
Abstract Twenty-three new α -aryl-β -nitroalkylphosphinates 3a - g were synthesized in high yields under very mild conditions. Compounds 3 consist of two pairs of diastereomeric isomers (A) and (B) 相似文献
5.
Yan-Ni Sun Cui-Ling Wang Ning Zhang Zheng Wang Zhu-Lan Liu Jian-Li Liu 《中国化学快报》2014,25(11):1503-1506
Tetrahydro-b-carbolines with strictosamide skeleton have been synthesized via intermolecular condensation, selective reduction, and intramolecular cyclization starting from phthalic anhydrides and tryptamine. The reactions are carried out under mild conditions with a wide range of substrates and functional groups. 相似文献
6.
Sierra D. Durham Brianna Sierra Maximillian J. Gomez Jennifer K. Tran Marc O. Anderson Nick A. Whittington-Davis Scott Eagon 《Tetrahedron letters》2017,58(28):2747-2750
The oxidation of tetrahydro-β-carbolines to β-carbolines using silver carbonate was developed as an alternative to current methods. The oxidation is extremely mild and provides the products in modest to good yields after purification. A number of functional groups are tolerated by this methodology, including reduction-sensitive groups which are often cleaved with other methods. Though the mechanism is not fully understood, the reaction proceeds in an open flask, is not sensitive to light or moisture, and provides a viable synthetic route to compounds that are not easily prepared via other methodologies. 相似文献
7.
B. B. Semenov K. A. Novikov A. N. Spitsin V. N. Azev V. V. Kachala 《Chemistry of Natural Compounds》2004,40(6):585-590
A diastereotopic Pictet—Spengler reaction was performed to form previously unknown 1- and 1,1-substituted 4-phenyl--carbolines based on -phenyltryptamine, aldehydes of various structure, and isatins. It has been demonstrated that the predominant diastereomers of the prepared -carbolines have the (R*,R*) configuration. The diasteroselectivity (de) of the reaction varies from 44 to 88%.Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 481–485, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
8.
A new class of 3-phenyl-4-substituted-β-carbolines via iodine-mediated electrophilic cyclization as key step were synthesized and their inhibitory activity against three tumor cell lines was evaluated in vitro.It was found that some of the tested compounds showed better cytotoxicity against HeLa and MCF-7 cells than harmine. 相似文献
9.
Peter Bernhardt 《Tetrahedron letters》2010,51(33):4400-8564
Strictosidine synthase triggers the formation of strictosidine from tryptamine and secologanin, thereby generating a carbon-carbon bond and a new stereogenic center. Strictosidine contains a tetrahydro-β-carboline moiety—an important N-heterocyclic framework found in a range of natural products and synthetic pharmaceuticals. Stereoselective methods to produce tetrahydro-β-carboline enantiomers are greatly valued. We report that strictosidine synthase from Ophiorrhiza pumila utilizes a range of simple achiral aldehydes and substituted tryptamines to form highly enantioenriched (ee >98%) tetrahydro-β-carbolines via a Pictet-Spengler reaction. This is the first example of aldehyde substrate promiscuity in the strictosidine synthase family of enzymes and represents a first step toward developing a general biocatalytic strategy to access chiral tetrahydro-β-carbolines. 相似文献
10.
Regiodivergent annulations of 3-phenoxy alkynyl indoles have been developed and tuned by protective groups through gold catalysis. With electron-donating protective groups, the substrate followed a C3-selective annulation and gave structurally interesting tetrahydro-β-carboline derivatives possessing potential bioactivity. Using electron-withdrawing protective groups, the substrate underwent a C2-selective annulation and afforded the structurally useful spiro-pseudoindoxyl found in natural indole alkaloids. Notably, an interesting and unusual 1, 2-migration of the phenoxy group was found in the C3-selective process. 相似文献
11.
The palladium-catalysed intramolecular α-arylation of carbonyl compounds with amino-tethered 2- and 3-iodoindoles provides a useful methodology for the synthesis of indolo-b-fused nitrogen heterocycles. A variety of substituted tetrahydro β- and γ-carbolines, and pyrrolo[3,4-b]indoles, have been prepared by means of this palladium-catalysed annulation process. 相似文献
12.
《中国化学快报》1997,(12)
KetaloracetalfonnationoproachingwiththecarbohydrasasreactantSarenowfrequentiyusedasanmprtanSyntheticmethodforprotedngofkbonesinthecourseforpreParationOfvariousmul~ctionalcomPlexorgamcmoledesl1-5].ThereaedonOfcyclicoraCyclicchiralcaIbohydrtesandtheirderivativeswithnon-methylarylketonescannotonlyproteCtndnylgrouPinarelkeone.butalsoInaketheira-carbonSUbedtutedcompoundstodiastercoisomericisomers,themolecularisomerscanalsobeeasilyconVertotinacontrolledfashion,toaseriesofpurelymul~edonalchiralm… 相似文献
13.
5-Fluorouracil (5-Fu,1)1 is an important antitumor drug. Some derivatives2,3 have shown better therapeutic efficacy than 5-Fu. In order to find much more better antitumor drugs of its derivatives, several attempts have been made and many different types of its derivatives have been prepared at N1, N3 position4~7. Moreover, several different ways have been used for alkylation of 5-Fu7~10. However, up to now, the arylation of 5-Fu at N1 or N3 position hasn't been reported, and the compound o… 相似文献
14.
A new methodology has been developed for the stereoselective preparation of β-aryl-β-boronyl α,β-unsaturated esters via Heck coupling, and their subsequent copper(I)-catalyzed enantioselective conjugate reduction. Various chiral secondary boronate derivatives can be accessed in excellent yields and good to high levels of enantioselectivity through the efficient copper-catalyzed process using polymethylhydrosiloxane (PMHS) as the hydride source. 相似文献
15.
16.
Mehdi Ghandi Mahdieh Mahami Ahangaran Alireza Abbasi 《Journal of the Iranian Chemical Society》2017,14(5):1131-1137
A one-pot five-component two-step sequential synthesis of tetrazole-based tetrahydrospiro[indene-2,1′-pyrido[3,4-b]indole]-1,3-diones in moderate to good yields is described. The reaction consists of four-component condensation of aromatic aldehydes with tryptamine, trimethylsilyl azide (TMSN3) and isocyanides, followed by addition of ninhydrin. These reactions presumably proceeded through Ugi-azide/Pictet–Spengler processes, respectively. 相似文献
17.
Lan TAO* Ling Li ZHANG Shui Jun SHEN Xiao Ping HAN Department of Chemistry Hangzhou Teachers College Hangzhou 《中国化学快报》2001,(9)
1, 2, 4- and 1, 2, 3-triazole derivatives have found wide applications as plant growth regulators1, bactericides and medical fungicides2, insecticides3 and in dyeing and color development4.One of the general routes of synthesis of 1-aryl-1, 2, 3-triazoles was to treat aryl azides with a-keto phosphorus ylides in dry refluxing benzene for 0.5 to 2 days5. Herein we report, for the first time, a very quick and simple, microwave-promoted synthesis of 1-aryl-1, 2, 3-triazoles 3 from aryl azides 1 an… 相似文献
18.
Keyur G. Brahmbhatt 《Tetrahedron letters》2009,50(39):5501-5504
Unprecedented aromatization was observed during N-alkylation reactions of 1-methyl-3,4-dihydro-β-carboline-3-carboxylic acid methyl ester, giving rise to 9-alkyl-1-methyl-β-carboline-3-carboxylic acid methyl esters. Inverse addition of base during a similar reaction resulted in a chemoselective alkylation to form novel 3-butyl-1-methyl-3,4-dihydro-β-carboline-3-carboxylic acid methyl ester as the major product in good yield. 相似文献
19.
Ziquan Zhao Yan Sun Lilin Wang Xuan Chen Yanpei Sun Long Lin Yulin Tang Fei Li Dongyin Chen 《Tetrahedron letters》2019,60(11):800-804
Organic base DBN has been identified as an efficient reagent for promoting the dehydrogenative/decarboxylative aromatization of tetrahydro-β-carbolines under air atmosphere, to access the corresponding β-carbolines in moderate to good yields. The utility of this protocol for the gram-scale synthesis of β-carboline alkaloids eudistomin U (7) and harmane (10) has also been demonstrated. 相似文献
20.
Takafumi Ohta Yuki Yamauchi Shoji Takitani 《Fresenius' Journal of Analytical Chemistry》1992,343(6):550-552
Summary The possibility of the fluorometric determination of hydrogen peroxide using various tetrahydro--carbolines as hydrogen-donating substrates for horseradish peroxidase was examined. A simple and sensitive method has been developed by using 1-methyl-1,2,3,4-tetrahydro--carboline-3-carboxylic acid as a substrate. The fluorescence intensity was proportional to the hydrogen peroxide concentration in the range of 0.05–1 mol/l (30–600 pmol/tube) in the sample solution with a relative standard deviation of 3.8% (0.1 mol/l). 相似文献