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21.
A method was developed for the synthesis of 2-oxo-4-phenyl-2,3-dihydro-9H-pyrimido[4,5-b]indole as well as of 2-chloro- and 2-nitramino-4-phenylpyrimido[4,5-b]indoles. The replacement of the chlorine atom in 2-chloropyrimidoindole gave rise to a number of its functional derivatives (morpholino, azido, and cyano). The reaction of 2-chloro-substituted pyrimidoindole with hydrazine hydrate and catalytic hydrogenation of 2-nitraminopyrimidoindole were studied.  相似文献   
22.
The readily available N-Boc arylhydrazines undergo efficient Fischer cyclizations to provide the indoles in good yields, when reacted with enolizable ketones.  相似文献   
23.
2,2-Dimethyl-3-(2-methyl-3-indolyl)cyclopropylacetic acid, its amide and esters, and the corresponding alcohol, viz., the product of ester reduction by LiAlH4, were synthesized. The chemoselectivity of N- and O-alkylation of these compounds was studied. Selective monoalkylation at the nitrogen atom of the heterocycle, O-alkylation to the side chain, or dialkylation at both nucleophilic sites can be carried out under conditions of phase-transfer catalysis. The N-acylation at the indole fragment of nitrile of this acid occurs only under the Vilsmeier—Haak formylation conditions.  相似文献   
24.
A sensitive and convenient high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) assay is described for the (5-HT(lB/lD)) receptor agonist sumatriptan in human plasma. Sumatriptan was recovered from plasma (81.8 +/- 6.8%) by liquid-liquid extraction. The mobile phase flow rate was 0.3 mL/min and consisted of methanol:water:formic acid (90:10:0.1, v/v/v). The analytical column (4.6 x 100 mm) was packed with Partisil C(8) (5 micro m). The standard curve was linear from 0.7 to 70.4 ng/mL (r(2) > 0.99). The lower limit of quantitation was 0.7 ng/mL. The assay was specific, accurate (percentage deviation from nominal concentrations were <15%), precise and reproducible (within- and between-day coefficients of variation <10.3%). Sumatriptan in plasma was stable over three freeze/thaw cycles and at room temperature for one day. The utility of the assay was demonstrated by following sumatriptan plasma concentrations in two healthy subjects for 8-12 h following a single 20 mg intranasal dose.  相似文献   
25.
For the purpose of organic syntheses of some corynanthe-type indole alkaloids, sesquiterpenes, and steroids, optically active intermediates cyclopentanone 3-allylalcohol, α-methylene-γ-butylo lactones andtrans-hydrindanone-propionic acid, were synthesized from (R)- and (S)-isopropylideneglyceraldehyde derived fromD-mannitol andLascorbic acid, respectively, utilizing Claisen rearrangement as a key reaction. Actually total syntheses of natural alkaloids, (-)-antirhine, (+)-dihydroantirhine and (-) dihydrocorynantheol were accomplished.  相似文献   
26.
一步法合成吲哚用Ag/SiO2催化剂的失活及其抑制   总被引:2,自引:0,他引:2  
 用简单浸渍法制备了Ag/SiO2催化剂.该催化剂对苯胺和乙二醇一步合成吲哚表现出很高的催化活性,但同时存在明显的失活.TG,XRD和TEM表征结果表明,催化剂失活的主要原因是反应过程中催化剂表面的积碳和银粒子的烧结.向反应体系中通入氢和水蒸气能够减少催化 剂表面的积碳;向催化剂体系加入ZnO助剂能较大程度地提高银的分散度,并能有效抑制反应过程中银粒子的烧结.  相似文献   
27.
金秋  尤启冬  唐锋 《结构化学》2013,32(7):1041-1045
The crystal structure of a new compound (Z)-N-(2-(diethylamino)ethyl)-7-(5- fluoro-2-oxoindolin-3-ylidene)-2-methyl-4,5,6,7-tetrahydro-1H-indole-3-carboxamidemethanol solvate (C24H29FN4O2CH4O, Mr = 456.55) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 14.560(3), b = 7.3200(2), c = 22.233(4) , β = 101.78(3)°, V = 2319.7(8) 3 , Z = 4, Dc = 1.307 g/cm 3 , F(000) = 976, μ = 0.092 mm -1 , MoKa radiation (λ = 0.71073), R = 0.0604 and wR = 0.1644 for 4262 observed reflections with I > 2 (I). X-ray diffraction analysis reveals that the indole and pyrrole are almost coplanar. Intramolecular C-H···O and N-H···O hydrogen bonds together with π-π interactions are found in the structure.  相似文献   
28.
以表雄酮为原料,经羟基氧化、羰基保护、还原、Fischer吲哚环化等反应合成了17-β-醇-雄甾-[3,2-b]-吲哚(5),总收率43.2%,其结构经1H NMR,IR和MS确证。生物活性初步测试结果表明:与雄诺龙相比,5对淡色库蚊的杀虫活性显著提高,在浓度为400 mg·L-1时,杀虫率为41.5%。  相似文献   
29.
Montmorillonite K10 was found to catalyze the Michael addition of indoles or pyrrole with nitroalkenes efficiently under solventless condition. The short reaction time, simple workup, and excellent yields were noteworthy. The green catalyst could be reused for three runs without considerable variation in yield.  相似文献   
30.
An expeditious synthetic method for the preparation of bis(indollyl)methane derivatives has been developed through a bismuth nitrate-catalyzed reaction of indole with various carbonyl compounds in mortar and pastle under solvent-free conditions.  相似文献   
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