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31.
Sridharan RajagopalMichael E Brooks Thach-Mien NguyenMichael Novak 《Tetrahedron》2003,59(40):8003-8010
We report the synthesis of N-acetoxy-N-(1-methyl-5H-pyrido[4,5-b]indol-3-yl)acetamide, 7, its N-pivaloyloxy analogue, 9, and improved synthesis of indole-2-acetonitrile, 3 (70% in five steps from indole-2-carboxylic acid), the carcinogenic amine Trp-P-2, 4 (40% from 3), and the nitro compound, 5 (40% from 4 by oxidation with H2O2 using Mo(CO)6 catalyst). In aqueous solution at neutral pH, 7 primarily undergoes C-O bond cleavage to yield the hydroxamic acid, 8, but under the same conditions the sterically hindered 9 decomposes predominately by N-O bond cleavage with a pH independent rate constant that is 7.5-fold smaller than that for 7. In the pH range 0.5-7.0 three different processes for the decomposition of 9 were detected by kinetics. Only the process that dominates at neutral pH generates a nitrenium species that can be trapped by N3−. 相似文献
32.
V. M. Kisel' M. O. Platonov E. O. Kostyrko V. R. Kovtunenko 《Chemistry of Heterocyclic Compounds》2000,36(8):905-910
A method has been developed for the synthesis of 4-[2-(bromomethyl)phenyl] tetrahydro-2H-4-pyrancarbonitrile and a study was carried out on the reaction of this compound with primary amines, which, depending on the conditions, leads to either 4-[2-(R-aminomethyl)phenyl]tetrahydro-2H-4-pyrancarbonitriles or hydrobromides of 2-R-aryl-2,3,2,3,5,6-hexahydrospiro[isoquinoline-4(1H),4-pyran]-3-imines.Taras Shevchenko Kiev University, 252017 Kiev, Ukraine; e-mail: vkysil@mail.univ.kiev.ua. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1035–1041, August, 2000. 相似文献
33.
二芳杂环基乙烯的合成及其光致变色反应研究 总被引:2,自引:0,他引:2
本文报道了2,3-双 (1,2-二甲基-3-吲哚基)-2-丁烯 (DF1),2,3-双 (1,4-二苯基-2-甲基-3-吡咯基)-2-丁烯 (DF2), 2,3-双(1-对甲苯基-4-苯基-2-甲基-3-吡咯基)-2-丁烯 (DF3), 2,3-双(1-对溴苯基-4-苯基-2-甲基-3-吡咯基)-2-丁烯 (DF4) 和2,3-双 (1-对甲氧苯基-5-苯基-2-甲基-3-吡咯基)-2-丁烯 (DF5) 的合成,以及它们的光致变色行为的研究。特别是DF1和DF5的光呈色和光消色过程进行了较为细致的研究。 相似文献
34.
35.
含氮杂环及其衍生物的氮氧化方法研究进展 总被引:1,自引:0,他引:1
含氮杂环及其衍生物中的N-氧化反应是合成许多精细化工产品,如日用化学 品、医药、农药的重要反应,但该反应选择性较高,只要求在杂环氮上进行氧化而 不影响分子其它部位,从氮杂环及其衍生物应用不同氧化剂选择性氧化综述了该类 化合物的N-氧化反应。 相似文献
36.
前文已报道某些1-酰基-4-取代氨基硫脲及其相关杂环衍生物具有广泛的生理活性,如抗结核,抗真菌,解痉挛及促进植物生长等功效。为进一步观察酰氨基硫脲及其杂环衍生物的有关活性,我们以β-吗啉丙酰肼(1)同一系列芳基异硫氰酸酯(2)进行反应,试图制得各种1-(β-吗啉丙酰基)-4-取代芳基氨基(3),并研究3在酸或碱性条件下的环化 相似文献
37.
I. Iovel L. Golomba J. Popelis S. Grinberga S. Belyakov E. Lukevics 《Chemistry of Heterocyclic Compounds》2002,38(10):1210-1229
We have studied condensation of 2-, 3-, 4-pyridinealdehydes and 6-methylpyridine-2-aldehyde with 2-aminopyridine and its 3-, 4-, and 6-methyl derivatives in benzene in the presence of molecular sieves. The reactions occur even at room temperature to form the corresponding pyridyl-pyridyl azomethines, and also aminals. We have determined the optimal conditions for carrying out the processes with the aim of obtaining both types of products. We consider the characteristics of the mass spectra for the synthesized aldimines. We present the X-ray diffraction results for the two aminals. 相似文献
38.
CrystalandMolecularStructureof3,4-diphenyl-5-ethyl-5-methyl-1,3,4-diazaphospholidin-2-thione-4-oxide¥FengKe-Sheng;ChenRu-Yu(I... 相似文献
39.
Electrospray ionization mass spectrometry was applied to the study of the amines IQ, Trp-P-1, Trp-P-2, PhIP and AC and the co-mutagens harman and norharman. The results obtained on a triple quadrupole mass spectrometer equipped with a pneumatically assisted electrospray source are reported. The chromatographic conditions were optimized with a reversed-phase column (1 mm I.D.) using acetonitrile-5 mM ammonium acetate (pH 6.7) (50:50) as the mobile phase at a flow-rate of 50 μl min−1. Different parameters influencing the mass spectra were investigated. For these compounds [M + H]+ in the positive-ion mode and also some fragments produced through collisionally activated decomposition in the interface were observed. Detection limits of 5.4–44 pg were obtained for standard solutions of these amines. Analysis of a meat extract was performed by HPLC-MS using single-ion monitoring after a solid-phase extraction clean-up. 相似文献
40.
Rosenani A. Haque Abbas Washeel Salman Srinivasa Budagumpi Amirul Al‐Ashraf Abdullah Zena A. Abdul Hameed Al‐Mudaris Amin M. S. Abdul Majid 《应用有机金属化学》2013,27(8):465-473
A series of Ag(I) complexes ( 6 , 7 , 8 , 9 ) derived from imidazol‐2‐ylidenes was synthesized by reacting Ag2O with an o‐, m‐, p‐xylyl or 1,3,5‐triazine‐linked imidazolium salts ( 1 , 2 , 3 , 4 ) and then characterizing these using various spectro‐analytical techniques. Additionally, triazine‐linked bis‐imidazolium salt 5 was characterized using the single‐crystal X‐ray diffraction method. Complexes 6–9 were formed from the N‐heterocyclic carbene ligand precursors 1–3 as PF6‐ salts in good yields. Conversely, salt 5 does not form Ag(I) complex even under various reaction conditions. Using ampicillin as a standard, complexes 6–9 were tested against bacteria strains Escherichia coli and Staphylococcus aureus as Gram‐negative and Gram‐positive bacteria, respectively, showing potent antimicrobial activities against the tested bacteria even at minimum inhibition concentration and bacterial concentration levels. Furthermore, the potential anticancer activities of the reported complexes were evaluated against the human colorectal cancer (HCT 116) cell lines, using 5‐fluorouracil as a standard drug. The highest anticancer activities were observed for complex 8 with an IC50 value of 3.4 μm , whereas the lowest was observed for complex 9 with an IC50 value of 18.1 μm . Copyright © 2013 John Wiley & Sons, Ltd. 相似文献