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哒嗪—3—酮类化合物的合成进展 总被引:1,自引:0,他引:1
综述了近年来哒嗪酮环骨架合成方法的研究进展,包括:1)由二羰基化合物合成;2)采用环加成反应;3)杂环转化法,以及其它方法,还叙述了哒嗪酮核苷的合成,参考文献22篇。 相似文献
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利用杂环金属盐法,通过呋喃碳核苷中间体,合成了哒嗪、哒嗪酮等碳核苷,讨论了反应机理;提高了呋喃汞盐法合成碳核苷的收率及立体选择性. 相似文献
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氟代哒嗪类化合物与有一定生理活性的氟代嘧啶类化合物有着同分异构的关系。而4-氟-3,6-二氯哒嗪又是合成其它药物的重要中间体。1984年田官荣报道了4-氟-3,6-二氯哒嗪的合成及同亲核试剂的反应性能和同类化合物 相似文献
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以取代苯和丁二酸酐为起始原料, 经Friedel-Crafts反应, 肼合环, Br2/HOAc氧化脱氢后得到一系列1,6-二氢-3-芳基-6-哒嗪酮(2a~2d). 然后将2a~2d与PCl5在POCl3中回流, 得到相应的氯代产物3a~3d, 将其与酰肼作用, 合环后得到一系列未见报道的哒嗪并[3,2-c]1,2,4-三唑类化合物. 所有化合物结构均经元素分析, IR, 1H NMR 和MS谱得以证实, 并对其波谱性质进行了讨论. 相似文献
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3-取代苄氧基-6-(取代-1H-吡唑-1-基)哒嗪的合成与生物活性 总被引:4,自引:0,他引:4
3-氯-6-肼基哒嗪分别与乙酰丙酮和3-二甲胺基丙烯醛反应, 合成了中间体3-氯-6-(3,5-二甲基-1H-吡唑-1-基)哒嗪(2)和3-氯-6-(1H-吡唑-1-基)哒嗪(4), 它们与多种取代苄醇反应, 得到了一系列未见报道的3-取代苄氧基-6-(取代-1H-吡唑-1-基)哒嗪, 其结构均经1H NMR, IR和元素分析确证. 初步的生物活性测试结果表明, 所合成的化合物对油菜和稗草均具有一定的抑制作用. 相似文献
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众所周知,许多嘧啶的核苷类化合物都有较强的生理活性,其中5-氟脲苷是有效的抗癌药。而哒嗪和嘧啶在结构上具有同分异构关系,因此,对于哒嗪核苷类化合物的合成及其生 相似文献
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New bent-core molecules with 4,6-dichlororesorcinol or 4-chloro-2-methylresorcinol as the central unit, and azobenzene with different alkyloxy chain length as side arms were synthesised. The mesophase behaviour of the new compounds was investigated by polarising optical microscopy, differential scanning calorimetry, X-ray diffraction studies and electro-optical measurements. It is found that 4,6-dichlororesorcinol is more conducive towards mesomorphism than 4-chloro-2-methylresorcinol. The liquid crystalline properties of all of the prepared compounds are greatly affected by the lateral substitution on the outer ring. 4,6-Dichlororesorcinol-based compounds without lateral substitution show nematic phases with cybotactic cluster of the SmC-type (NCybC). Moreover, depending on the chain length, the nematic phase appears as enantiotropic phase for the shortest homologue and as monotropic phase for the higher homologues. 相似文献
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K.C. Majumdar Pranab K. Shyam D.S. Shankar Rao S. Krishna Prasad 《Liquid crystals》2013,40(11):1358-1367
The synthesis and liquid crystalline properties of novel chiral Schiff's base dimers containing the 1,3,4-oxadiazole ring are reported. The length of the terminal S-alkyl chain has been varied. All the compounds synthesised were thermally stable and exhibited enantiotropic mesomorphism, showing either SmC*–SmA–TGB–N*–BP or SmC*–SmA phase sequence. 相似文献
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A. F. Mishnev Ya. Ya. Bleidelis É. É. Liepin'sh N. P. Ramzaeva I. N. Goncharova 《Chemistry of Heterocyclic Compounds》1979,15(7):798-804
The reaction of 4-chloro-5-amino-6-(1,3-dihydroxy-2-propyl)aminopyrimidine with excess ethyl orthoformate gave a cyclic acetal, viz., 6-chloro-9-(2-ethoxy-1,3-dioxan-5-yl)purine, amination of which yielded 6-amino-9-(2-ethoxy-1,3-dioxan-5-yl)purine. The presence of two configurational isomers with a diaxial orientation of the purine ring and the ethoxy group in the trans isomer and an equatorial orientation of the ethoxy group in the cis isomer was established for these compounds by 1H and 13C NMR and IR spectroscopy. The three-dimensional structure of trans-6-chloro-9-(2-ethoxy-1,3-dioxan-5-yl)purine was determined by an x-ray difraction study, and the trans-diaxial orientation of the purine ring and the ethoxy group was confirmed; it is shown that the dioxane ring is in an anti conformation relative to the purine ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 976–983, July, 1979. 相似文献
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Yoshihisa Kurasawa Akiko Takano Kyoko Kato Atsushi Takada Ho Sik Kim Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1996,33(3):757-762
The reaction of 6-chloro-2-(l-methylhydrazino)quinoxaline 1-oxide 3 with acetylenedicarboxylates gave the 8-chloro-1-memyl-1,5-dihydropyridazino[3,4-b]quinoxaline-3,4-dicarboxylates 4a,b and 2-(pyrazol-4-yl)quinoxaline 1-oxides 5a,b . The formation of compounds 4a,b would follow the 1,3-dipolar cycloaddition reaction, subsequent 1,2-hydrazino migration, and then dehydrative cyclization, while the production of compounds 5a,b would proceed via the addition of the hydrazino group to acetylene-dicarboxylate leading to the construction of a pyrazole ring, followed by rearrangement of the pyrazole ring. Compounds 5a,b were deoxidized with phosphoryl chloride/N,N-dimethylformamide to change into the 4-(quinoxalin-2-yl)pyrazole-3-carboxylates 8a,b . 相似文献
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It was found that various organic compounds and inorganic salts added in small concentrations to aqueous solutions increase
the quantum yields of photochemical chain ion-radical reactions of the sulfo group substitution for a halogen in halogenated
naphthylamine (4-chloro-1 -naphthylamine) and hydroxynaphthalenes (1-bromo-2-hydroxynaphthalene and 4-chloro-2-hydroxynaphthalene).
An increase in the quantum yield of the photosubstitution chain reaction of the sulfo group for a halogen on the aromatic
ring in the presence of low concentrations of organic compounds and inorganic salts is a phenomenon common to various substrates
in both direct and sensitized photolysis. Neither organic compounds nor inorganic salts in low concentrations affect the fluorescence
of substrates and the chain length of the substitution reaction. It is suggested that the main effect of small additives on
the photochemical chain reaction is due to a change in the reactivity of ionradical pairs, the primary products of a photoinduced
electron transfer reaction at the initiation step. 相似文献
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《Liquid crystals》1999,26(3):389-396
Two series of calamitic liquid crystals containing a benzothiazole ring within the central core and two different linkage groups (amide and azo) have been prepared and their liquid crystalline properties studied and compared with those of the analogous series of imines. The influence of the linkage group within the central core has been proven to determine the variety of mesomorphism displayed by the compounds. The compounds with imine and azo linkages behave in a similar way and exhibit typical nematic and smectic C mesophases. Compounds incorporating an amide linkage show a poorer mesomorphism and mainly present a smectic C mesophase. 相似文献
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Himani N. Chopde Chandrashekhar P. Pandhurnekar Babita G. Yadao Doyel M. Bhattacharya Arvind J. Mungole 《Journal of heterocyclic chemistry》2020,57(9):3499-3504
One-pot synthesis of 1-([6-bromo-2-hydroxy-naphthalen-1-yl]-aryl-phenyl)methyl)-3-chloro-4-(aryl-phenyl)azetidin-2-ones has been reported in the present research work via Staudinger [2 + 2] ketene-imine cycloaddition reaction pathway. The reaction of 1-((Benzylideneamino)(aryl)methyl)-6-bromo-naphthalen-2-ols with chloroacetic acid and triethylamine afforded 1-([6-bromo-2-hydroxynaphthalen-1-yl]aryl-phenyl)methyl)-3-chloro-4-(aryl-phenyl)azetidin-2-ones. For the structural elucidation of series of compounds, different analytical and spectroscopic techniques such as elemental analysis, IR spectra, 1H-NMR spectra and mass spectra were used. All the newly synthesized compounds were tested for their anti-bacterial activity studies. It revealed that some of the compounds possesses moderate to good activities as compared to standard drugs. The widest spectrum of anti-bacterial activities against both gram-positive and gram-negative bacterial strains among the examined compounds possessed having more hydroxyl group along with β-lactam ring compared to other substituted azetidinones. 相似文献
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M. N. Sheng 《Journal of heterocyclic chemistry》1969,6(5):651-654
The base catalyzed isomerizations of epichlorohydrin, 1-chloro-2,3-epoxy-2-methylpropane, 1-chloro-2,3-epoxybutane, and 3-chloro-1,2-epoxybutane have been studied, using lithium ortho-phosphate as the basic catalyst. Chloroketones and dichloro-alcohols are the major products. This is the first example of a compound with an electron withdrawing group attached to the carbon atom adjacent to the oxirane ring which undergoes the α-elimination pathway. A bidirectional mechanism is proposed to explain the experimental results. The stereochemistry of the hydrochlorination of 1-chloro-2,3-epoxybutane and 3-chloro-1,2-epoxybutane has also been studied. 相似文献