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531.
532.
ZHAO Qing-Jiea LIN Hai-Xiaa② HAN Naa CHEN Min-Qinb YANG Ming-Faa a 《结构化学》2005,24(6):701-705
1 INTRODUCTION The Koevenagel condensation catalyzed by bases or Lewis acid has been the subject of many synthetic applications since its discovery[1] although the pre- sence of catalyst is not always indispensable[2]. Mo- reover, the reaction of aromatic aldehyde with 1,3- cyclohexanedione under different conditions afforded different products[3~6]. In continuing efforts for the application of 1,3-cyclohexanedione derivatives to construct new heterocycles with biological activi- ties[7… 相似文献
533.
LI Hao-Honga CHEN Zhi-Rong ② WANG Canga REN Yong-Ganga LI Jun-Qiana b HUANG Chang-Canga ZHAO Bina a 《结构化学》2005,24(11):1318-1323
1 INTRODUCTION The importance of metal ions in nucleic acid and other biologic processes has stimulated considerable research interest in the area of metal interactions with nuclei acid constituents[1, 2] due to the discovery that some platinum compounds, especially cis-Pt (NH3)2- Cl2, exhibit carcinostatic properties[3]. This has led to an increased research activity in the chemistry and structures of platinum complexes containing novel or- ganic ligands. And crystal engineering has its… 相似文献
534.
ZHANG Jing-Laia WU Wen-Penga WANG Lian-Bina CAO Ze-Xingb② a 《结构化学》2005,24(8):885-894
1 INTRODUCTION Carbon-chain species are widely present in the interstellar medium as possible carriers of the diffuse interstellar bands. They play an important role in diverse chemical processes and nanoscience as intermediates and building units. Because of their high reactivity, bare carbon chains are readily termi- nated by a wide variety of atoms, forming XCn or XCnX linear clusters[1]. During the past decade, lots of theoretical spectra of different carbon chain systems have been … 相似文献
535.
1INTRODUCTIONThehydrothermalsynthesisofmetalsaltsofaro-maticpolycarboxylicacidisattractinginterestinthefieldofcrystalengineeringasaconsequenceoftheirnovelstructuresandpropertiessuchasporosityandmagneticinteractionsbetweenparamagneticmetal-ions[1~7].1,3,5-Benzenetricarboxylicacid(H3-BTC)hasreceivedconsiderableattentionasatridentatearomaticpolycarboxylicligandcapableofformingcoordinationpolymers.Manyscientistshavesuc-ceededinsynthesizingvarietyofporouscoordina-tionpolymerswithhighdimension… 相似文献
536.
537.
ZHANG Xing-Chuana YU Jinga WANG Zun-Yaoa② LIU Hong-Xiab a 《结构化学》2006,25(7):823-829
1 INTRODUCTION Quantitative structure-activity relationship (QSAR) equation could be employed to predict the biological activities of unknown compounds, which is signifi- cant for initial screening and evaluation of toxic compounds[1]. Soil sorption coeff… 相似文献
538.
ElectronIonizationMasSpectrometryofSomeFerrocenylThia┐crownEthersSUJing-zheandJUYing(BeijingInstituteofChemicalReagents,Beiji... 相似文献
539.
1 INTRODUCTION The replacement reactions between halide and hy- drogen halide, or halide and halide are basic reac- tions in chemistry. Goldfinger et al. have speculated by experiment that the gas reaction between chlorine and hydrogen bromide might be a two-step intermo- lecular reaction[1, 2]. But gas reactions between other halides and hydrogen halides haven’t been reported experimentally so far. About theoretical investiga- tion, colinearity quantum mechanics, vibrational tran- sitio… 相似文献
540.
1 INTRODUCTION Niflumic acid (2-[3-(trifluoromethyl) phenyl] amino nicotinic acid, HNifa) is an organic fluoro compound used in the preparation of ‘Donalgin’ as the active substance. In medicine, HNifa has been widely used as a non-steroidal anti-inflammatory analgetic drug[1]. The extensive application of this preparation in medical practice has attracted much interest in other various biological fields such as the determination in serum, urine[2~4], and coordination behaviors with … 相似文献