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71.
A new Sequiterpenoid from Eupatorium adenophorum Spreng 总被引:1,自引:0,他引:1
A new sequiterpenoid compound 8aα-hydroxy-1-isopropyl-4,7-dimethyl-1,2,3,4,6,8a-hexahydro-naphthalene-2,6-dione(1),together with seven known compounds anti-HH-dimer-coumarin(2),(-)-5-exo-hydroxy-bomeol(3),O-hydroxyl cinnamic acid(4),9β-hydroxy-ageraphorone(5),10Hα-9-oxo-ageraphorone(6),10Hβ-9-oxo-ageraphorone(7)and 9-oxo-10,11-dehydroageraphorone 8,was isolated from the leaves of Eupatorium adenopho-rum Spreng.The structures were elucidated by IR,~1H and ~(13)C NMR,EIMS,HMBC and single-crystal X-ray spec-tral data. 相似文献
72.
Porous anodic alumina (PAA) was used as a template to prepare Co nanowires array from 1-ethyl-3-methylimidazolium chloride ionic liquid by direct current method. The surface morphology of porous anodic alumina template was observed by field emission-scanning tunneling microscopy (FE-SEM) before and after the electrodeposition of Co nanowires. The electrodeposition of Co nanowires was characterized by transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). TEM results indicate that the Co nanowire surface is coarse and porous when aqueous solution was used as electrolyte, and the Co nanowire deposited from the ionic liquid is uniform and smooth. XRD results show that the electrodeposition of Co is a mixture of crystal and microcrystal phase. 相似文献
73.
通过原子转移自由基聚合方法, 在丁酮/异丙醇混合溶剂中合成了分子量可控和分布较窄的聚丙烯酸叔丁酯-b-聚N-异丙基丙烯酰胺(PtBA-b-PNIPAM)嵌段共聚物, 用GPC和 1 H NMR对其结构进行了表征. PtBA-b-PNIPAM在甲苯中水解得到聚丙烯酸-b-聚N-异丙基丙烯酰胺(PAA-b-PNIPAM). 用动态光散射技术对PAA-b-PNIPAM在水溶液中的自组装行为随pH值和温度变化的响应进行了初步研究. 相似文献
74.
表面引发原子转移自由基聚合方法合成Fe3O4/PMMA复合纳米微粒 总被引:7,自引:1,他引:7
采用表面引发原子转移自由基聚合方法合成了核壳结构的磁性高分子纳米微粒. 作为聚合反应引发剂的3-氯丙酸, 首先与油酸修饰的Fe3O4纳米微粒表面的部分油酸置换, 然后在Fe3O4纳米微粒表面引发甲基丙烯酸甲酯聚合, 合成的纳米复合材料用TEM, FTIR, XRD和DSC表征. 磁性测试结果表明, 所制备的磁性高分子纳米微粒仍具有超顺磁性, 但由于聚合物的存在, 其饱和磁化强度降低. 相似文献
75.
V. A. Dorokhov M. F. Gordeev A. V. Komkov V. S. Bogdanov 《Russian Chemical Bulletin》1991,40(11):2267-2273
The action of alkyl and aryl isocyanates on the N,S-acetals of diacetylketene leads to the formation of 4-alkylthio-5-acetyl-1-alkyl(aryl)-6-methyl-1H-pyrimidin-2-ones (derivatives of 4-alkylthiouracils). The reaction of the synthesized thiouracils with amines or the reaction of the N,N-acetals of diacetylketene (N,N-ADK) with an equi-molar amount of aryl isocyanates leads to the formation of substituted 4-amino-5-acetyl-1H-pyrimidin-2-ones (derivatives of cytosine). From the latter and isocyanates or directly from N,N-ADK and an excess of the isocyanate, derivatives of 4-methylene-1H,3H, 4H-pyrimido[4,5-d]pyrimidine-2,7-dione were obtained. The exception was the condensation of 3-[N-(4,6-dimethyl-2-pyrimidinyl)diaminomethylene]pentane-2,4-dione with aryl isocyanates, which led to 3H,8H-pyrido[2,3-d]pyrimidine-2,5-diones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2593–2599, November, 1991. 相似文献
76.
77.
K. L. Cherkasova V. S. Bogdanov V. A. Dorokhov O. V. Shishkin 《Russian Chemical Bulletin》1996,45(6):1437-1439
4-Methylthiopyrido[1,2-α]pyrimidin-2-one and 2-hydroxypyrido[1,2-α]pyrimidine-4-thione derivatives were synthesized by the addition ofN-(4-R-pyrid-2-yl)acetoacetamides (R = H, Me) to CS2 under phase-transfer conditions followed by the alkylation of the reaction products with Mel. The molecular structure of 3-acetyl-4-methylthiopyrido[1,2-α]pyrimidin-2-one is established by X-ray analysis. 相似文献
78.
A. N. Andreyev D. D. Bogdanov V. I. Chepigin A. P. Kabachenko O. N. Malyshev Yu. Ts. Oganessian R. N. Sagajdak G. M. Ter-Akopian A. V. Yeremin F. P. Hessberger S. Hofmann V. Ninov M. Florek S. Saro M. Veselsky 《Zeitschrift für Physik A Hadrons and Nuclei》1992,344(2):225-226
The neutron-deficient isotopes257,258105 were produced in the reaction27Al+236u in 6n and 5n evaporation channels, respectively. The evaporation residues emerging from the target were separated in-flight from the projectiles and from products of different nuclear reactions by the electrostatic separator VASSILISSA [1]. The isotopes were then implanted into position-sensitive silicon detectors and identified using the --correlation method. The measured production cross-section is (5n)=(0.45±0.20)nb atE
P
=154 MeV and (6n)=(0.075±0.055) nb atE
P
=163 MeV. These cross-sections are compared with data measured for the same isotopes in the more symmetrical reaction50Ti+209Bi. 相似文献
79.
A. A. Dudinov L. I. Belen'kii V. S. Bogdanov B. I. Ugrak M. M. Krayushkin 《Chemistry of Heterocyclic Compounds》1990,26(9):1043-1047
Oximes of 3,3-dichloropropenal and 4,4,4-trifluoro-3-chloro-1-butenal were obtained on the basis of products of free-radical addition of CCl4 and CF3CCl3 to vinyl butyl ether. Generation of the corresponding nitrile oxides from these oximes and reaction of the nitrile oxides in situ with vinyl butyl ether, phenylacetylene, and propargyl alcohol via the scheme of 1,3-dipolar cycloaddition are proposed as a method for the synthesis of isoxazoles containing ,-dichlorovinyl and -trifluoromethyl--chlorovinyl substituents in the 3 position.See [1] for Communication 1.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1250–1255, September, 1990. 相似文献
80.
V. S. Bogdanov A. M. Turuta E. G. Cherepanova T. M. Fadeeva A. V. Kamernitsky A. A. Korobov 《Russian Chemical Bulletin》1993,42(1):194-198
13C NMR spectra of epimeric 17-R-substituted 17-ethynylandrostenes (R = H, OH, OAc, OMe, NCS) and 17-R-substituted 17-ethynylandrostenes (R = H, OH, OAc, OMe), and their hexacarbonyldicobalt complexes, as well as of 16-17-ethynylandrostenes and their hexacarbonyldicobalt complexes have been studied. Stereochemical dependence of C(12), C(14), C(18), C(20) and C(21) chemical shifts on the configuration of the substituents at C(17) has been demonstrated. The effect of Co-complexation on the spectral characteristics of Co-coordinated 17-ethynylandrostenes in both Stereochemical series has been investigated.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 212–216, January, 1993. 相似文献