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101.
The design, synthesis and evaluation of a pentacyclic scaffold, CWO-324 to mimic saframycin A is described. CWO-324 is readily synthesized in five steps from 1,4-diacetyl-piperazine-2,5-dione and 2,5-dimethoxybenzaldehyde. CWO-324 was found to scission DNA, binds to bases 69-83(5′-GCAGTCAGG CACCGT-3′) of Hind III/Rsa I from plasmid pBR322 DNA in a foot-printing study and possesses anti-tumor activity. 相似文献
102.
By means of a large-scale molecular dynamics simulation, we show that the Tolman length, although positive, is much smaller in magnitude than previously reported. We found that the range of interparticle interaction can significantly affect the magnitude of the Tolman length. When the range of interaction is longer than five molecular diameters, the Tolman length is on the order of a few hundredths of the molecular diameter, rather than a few tenths known previously. 相似文献
103.
M. F. Shostakovskii G. G. Skvortsova V. V. An Yu. A. Mansurov 《Chemistry of Heterocyclic Compounds》1969,5(1):6-7
Vinyl-furancarboxylate has been synthesized by the reaction of-furancarboxylic acid with acetylene and with vinyl acetate in the presence of various catalysts. The structure of the vinyl ester has been confirmed by IR spectra and by catalytic hydrogenation. The acid and alkaline hydrolyses of vinyl-furancarboxylate have been studied. 相似文献
104.
铕对小麦根细胞钙调素及NAD激酶的影响研究 总被引:2,自引:0,他引:2
研究了Eu对小麦根细胞内钙调素的含量和活性以及对受钙调素调控的专一性酶NAD激酶的影响。结果表明,Eu^3+有类似Ca^2+的作用,影响受Ca^2+浓度调控的信号系统关键蛋白——钙调素的活性和含量变化。从而引起钙调素调控酶NAD激酶的活性改变,最终影响细胞内生理生化过程。认为稀土离子对生物体的Hormesis效应町能与稀土离子对细胞信号传递系统的影响有关,稀土离子可能通过影响细胞信号系统来调节细胞内的各种生理生化变化,形成稀土元素生物效应的多样性特征。 相似文献
105.
新型有机锗倍半氧化物及硫化物的合成 总被引:1,自引:0,他引:1
已先后合成的倍半氧化物类及倍半硫化物类化合物的前体,即有机锗三氯化物中只含1个锗原子。为了考查从含2个锗原子的前体合成的有机锗倍半氧化物及硫化物的药物活性,我们合成了1类化合物及相应的倍半氧化物(2类)及倍半硫化物(3类),并合成了酰基苯胺化合物1_e、2_e及3_e。结果见表1。 相似文献
106.
107.
A mixture of six biphenyl nitrile compounds and three related substances with high hydrophobicity and similar structures was successfully separated by microemulsion electrokinetic chromatography (MEEKC) within 30 min. The microemulsion system contained 100 mM sodium dodecyl sulfate (SDS), 80 mM sodium cholate (SC), 0.81% v/v heptane, 7.5% v/v n-butanol, 10% v/v acetonitrile, and 10 mM borate. The addition of SC, organic modifiers, sample preparation, and temperature all showed remarkable effects on the separation. The capacity factor (k) was calculated by using dodecyl benzene as the marker for microemulsion, and the calculated partition coefficient log P(o/w) of the solutes was in the range of 3.35-7.38. The log k values matched well with the log P(o/w) with a correlation coefficient of 0.96. In addition, the linear correlation coefficients of each compound between peak area and concentration were from 0.996 to 0.998 with the repeatability RSD value < 1.2% for migration time and < 4.8% for peak area, and the highest theoretic plate number was > 586000. MEEKC was compared with micellar electrokinetic chromatography (MEKC) indicating that the former method is more suitable for this separation and can be used for the quality control of biphenyl nitrile compounds in the synthesis of liquid crystals. 相似文献
108.
N—(β—羧丙酰基)异鲁米诺的电致化学发光行为及其机理探讨 总被引:1,自引:0,他引:1
本进行了N-(β-羧丙酰基)异鲁米诺的电致化学发光行为的研究。采用正矩形液脉冲电压,在KOH-KCl-H2O2-(pH11.6)介质中,N-(β-羧丙酰基)异鲁米诺测定的线性范围为4.0×10^-10 ̄7.0×10^-8mol/L,检出限为2.0×10^-10mol/L。本对此体系的电致化学发光机理进行了探讨。 相似文献
109.
A.J. Leusink G. An Koten J.W. Marsman J.G. Noltes 《Journal of organometallic chemistry》1973,55(2):419-425
Bis{2-[(dimethylamino)methyl]phenyl}silverlithium has been prepared and characterized. Molecular weight determinations, and 13C NMR and 1H NMR spectra reveal that the compound exists (in benzene) as a tetranuclear mixed metal cluster containing aryl groups bridging the silver and lithium atoms. Silver-proton, silver-carbon and lithium-carbon couplings have been observed in the NMR spectra of this compound. 相似文献
110.
AnLIU ZhongMeiZOU LiZhenXU ShiLinYANG 《中国化学快报》2003,14(11):1144-1145
A new compound, subglain B, was isolated from the stems of Uvaria tonkinensis var.subglabra and its structure was identified as 1S, 2R, 3S, 6R-1-benzoyloxymethylene-1,2-dihydroxy-3-benzoyloxy-6-chlorocyclohex-4-ene (1), by spectral evidences. 相似文献