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611.
The main purpose of the development of an Rh(I) Carbonyl Phosphine force field was to predict the molecular structure of Rh(I) complexes as well as to compute possible intermediates or transition states during the oxidative addition of CH3I to these complexes. © 2000 John Wiley & Sons, Inc. J Comput Chem 21: 692–703, 2000  相似文献   
612.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   
613.
Viral hepatitis is a common infectious disease caused by five viruses (hepatitis virus A, B, C, D, and E). Given the diversity of hepatitis virus, rapid screening and accurate typing of viral hepatitis are the prerequisites for hepatitis therapy. Here, a multicolor fluorescence system was constructed by combining with the multi-color fluorescence properties of CdSe/ZnS quantum dots (QDs, emission wavelengths: 525 nm, 585 nm and 632 nm) and the broad-spectrum fluorescence quenching performance of GO. Taking advantage of the specific recognition of ssDNA modified CdSe/ZnS QDs to target hepatitis virus DNA, the constructed system could effectively distinguish hepatitis A virus DNA (HAV-DNA), hepatitis B virus DNA (HBV-DNA), and hepatitis C virus DNA (HCV-DNA) in a homogeneous solution. Based on the different adsorption property of GO for ssDNA and dsDNA, the fluorescence Forster resonance energy transfer (FRET) process between ssDNA modified QDs and GO could be regulated. The fluorescence signal of the constructed system presented a sensitive response to HAV-DNA, HBV-DNA, and HCV-DNA content in the range of 1.0–192 nM, 8.0–192 nM, and 1.0–128 nM, respectively. The limit of detection for HAV-DNA, HBV-DNA, and HCV-DNA is 0.46 nM, 1.53 nM, and 0.58 nM. The constructed system can be used to screen hepatitis virus DNA in real samples, which provides an alternative strategy for rapid screening and diagnosis of viral hepatitis.  相似文献   
614.
The title gallides are prepared from the elements by induction melting and subsequent annealing (Ta ampules, 800 mbar Ar, 873—1073 K, 4 d) and characterized by powder and single crystal XRD.  相似文献   
615.
The development of environment-friendly, step economic couplings to generate structurally diverse macrocyclic compounds is highly desirable but poses a marked challenge. Inspired by the C−H oxidation mechanism of cytochromes P450, an unprecedented and practical RhIII-catalyzed acylmethylation macrocyclization via C−H/O2 dual activation has been developed by us. The process of macrocyclization is facilitated by a synergic coordination from pyridine and ester group. Interestingly, the reaction mode derives from a three-component coupling which differs from established olefination and alkylation paths. Density functional theory (DFT) calculations and control experiments revealed the mechanism of this unique C−H/O2 dual activation. The newly achieved acylmethylation macrocyclic products and their derivatives showed a potent anti-H1N1 bioactivity, which may provide an opportunity for the discovery of novel anti-H1N1 macrocyclic leading compounds.  相似文献   
616.
The title compounds are prepared by arc‐melting of the elements and subsequent annealing (evacuated silica tube, 970 K, 5d).  相似文献   
617.
Rhodium(III)-catalyzed cross-dehydrogenative coupling involves a highly efficient C−C bond formation from N-phenyl-7-azaindole frameworks, thiophenes. Various novel 7-azaindole derivatives have been successfully developed with good substrate applicability.  相似文献   
618.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   
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