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611.
WANG Wen-Qinga② GONG Yana WANG Zhe-Mingb YAN Chun-Huab a 《结构化学》2003,22(5):539-544
1 INTRODUCTION D-amino acids are universally present and play different biological roles in various organisms in- cluding those in the human body. Milton[1] has shown that the D and L forms of the enzyme HIV-1 protease were equally affected by the achiral inhi- bitor but displayed reciprocal chiral specificity in their biochemical interactions. D-proteins may also be nonimmunogenic. Senility and some diseases are related to D-amino acids, such as renal disease[2], Alzheimer disease[3… 相似文献
612.
1 INTRODUCTION Procedures to synthesize copper(I) complexes are of great interest due to the diversity of products resulting from almost the same methodology. It has been long known that four-electron-donordipho- sphine compounds Ph2P(CH2)nPPh2 are excellent bi- dentate ligands[1, 2]. The chelating tendency of bis- (diphenylphosphino) methane is one of the dipho- sphine ligands most suitable to lock two metal atoms together in close proximity[3]. Many examples of bi- or polynuclear com… 相似文献
613.
1INTRODUCTIONThehydrothermalsynthesisofmetalsaltsofaro-maticpolycarboxylicacidisattractinginterestinthefieldofcrystalengineeringasaconsequenceoftheirnovelstructuresandpropertiessuchasporosityandmagneticinteractionsbetweenparamagneticmetal-ions[1~7].1,3,5-Benzenetricarboxylicacid(H3-BTC)hasreceivedconsiderableattentionasatridentatearomaticpolycarboxylicligandcapableofformingcoordinationpolymers.Manyscientistshavesuc-ceededinsynthesizingvarietyofporouscoordina-tionpolymerswithhighdimension… 相似文献
614.
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
615.
LUO Meia MA Huai-Zhub SU Qing-Dea① LI Qian-Ronga a 《结构化学》2002,21(5):538-540
1 INTRODUCTION 6-Bromo-piperonal-dimethyl-acetal is an intermediate used for the synthesis of natural products, such as podophyllotoxin[1] and the related compounds[2~6] due to the useful biological activities associated with some of its derivatives[7, 8]. In particular, glycoside derivatives of 4?dimethyl- 4-epipodophyllotoxin have been used in cancer chemotherapy[9, 10]. The title compound has been synthesized from raw material piperonal, after bromo substitution and acetal protection… 相似文献
616.
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
617.
ElectronIonizationMasSpectrometryofSomeFerrocenylThia┐crownEthersSUJing-zheandJUYing(BeijingInstituteofChemicalReagents,Beiji... 相似文献
618.
1 INTRODUCTION Low-valent titanium reagents have exceedinglyhigh abilities to promote reductive coupling of car-bonyl compounds and they are attracting increasinginterest in organic synthesis[1]. Many other func-tional groups can also be coupled[2~8]. Recently, wehave reported some intermolecular reductive cou-pling reactions[9~12] and some new intramolecular re-ductive coupling reactions[13~16] induced by low-va-lent titanium reagents. The spiro[4.4]nonane skeleton has been found inmany… 相似文献
619.
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
620.
1 INTRODUCTION The rational design and synthesis of new metal- organic frameworks have generated considerable interest in supramolecular chemistry and materials science owing to their intriguing structural diver- sities and potential applications as functional mate- rials[1~6]. Carboxylate-containing ligands have attrac- ted considerable attention because of the various coordination modes of carboxylate group, the ability to form hydrogen bonds and the potential applica- tions as functio… 相似文献