- Syntheses and structural studies of heterobimetallic thiocarboxylate complexes containing zinc and silver
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Novel heterobimetallic complexes, [(PPh3)2Ag(μ- SCOth)2Zn(SCOth)(H2O)] (1) and {[(PPh3) 2Ag(μ-SCOPh)2Zn(SCOPh)(H2O)][(PPh 3)2Ag(μ-SCOPh)Zn(SCOPh)2]} (2) have been prepared and characterized by FTIR, 1H, 13C and 31P NMR spectroscopy. Molecular structures of the complexes have been determined by single crystal X-ray diffraction technique. In these complexes the two metal atoms (Ag and Zn) are held together by bridging (μ-S or μ-O,S) thiocaboxylate groups. The terminal thiocarboxylate ligand binds monodentately (through S) in 1. Structure of 2 is unique as two different molecules, [(PPh3)2Ag(μ-SCOPh)Zn(SCOPh)2] and [(PPh3)2Ag(μ-SCOPh)2Zn(SCOPh)H 2O] co-crystallize in the same lattice. The terminal thiocarboxylate ligand is monodentate (S) in the latter while bidentate (O,S) in the former molecule. Electronic spectral behaviors of the complexes have been explained by TDDFT calculations. Luminescence properties of both have been studied in solid state.
- Singh, Suryabhan,Chaturvedi, Jyotsna,Bhattacharya, Subrato
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- METHODS TO INCREASE THE PHOTOSTABILITY
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The presently disclosed subject matter provides dyes having an improved photostability, biosensors comprising such dyes, and methods of use thereof, including methods for detecting target molecules in a sample under test and for live- cell imaging. The dyes can include a binding member, including a biomolecule or fragments thereof, which can interact with target molecules of interest and can be specific to a given conformational state or covalent modification, e.g., phosphorylation, of the target molecule. The presently disclosed dyes can be used for detecting changes in the binding, conformational change, or posttranslational modification of the target molecule.
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Page/Page column 72; 75-76
(2009/01/23)
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- Effect of modification of the electrophilic center on the α effect
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We report on a nucleophilic study of esters R-C(=X)-Y-Ar in which the electrophilic center has been modified by replacing O by S in the leaving group or carbonyl center: 4-nitrophenyl acetate (1), S-4-nitrophenyl thioacetate (2), 4-nitrophenyl benzoate (3), and O-4-nitrophenyl thionobenzoate (4). The studies include O- and S- nucleophiles as well as α nucleophiles in H2O at 25.0 ± 0.1°C. The sulfur nucleophile (4-chlorothiophenoxide, 4-ClPhS-) exhibits significant enhanced reactivity for the reactions with thiol and thione esters 2 and 4 compared with their oxygen analogues 1 and 3. On the contrary, the common nucleophile OH- is much less reactive towards 2 and 4 compared with 1 and 3. The effect of changing both the electrophilic center and the nucleofugic center on the reactivity of the other oxygen nucleophiles is not so significant: 4-chlorophenoxide (4-ClPhO-) is four to six times more reactive in the reactions with thiol and thione esters 2 and 4 compared with their oxygen analogues 1 and 3. The α effects exhibited by butan-2,3-dione monoximate (Ox-) and HOO- are strongly dependent on the nature of the electrophilic center of the substrates, indicating that the difference in the ground-state solvation energy cannot be fully responsible for the α effect. Our results clearly emphasize the strong dependence of the α effect on the substrate structure, notably, the nature of the electrophilic center. The impact of change in the nucleofuge (1-→2) and the electrophilic center (3-→4) on reactivity indicates that anucleophiles will need to be "purpose built" for decontamination and nucleophilic degradation of specific biocides.
- Um, Ik-Hwan,Lee, Ji-Youn,Bae, Sun-Young,Buncel, Erwin
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p. 1365 - 1371
(2007/10/03)
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- 3'-(2')-amino or thiol-modified, fluorescent dye-coupled oligonucleotides and a process for the preparation and the use thereof
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The OH group located in the 3' and/or 2' position of a nucleoside, nucleotide or oligonucleotide is derivatized to an amino or thiol group and subsequently a fluorescent dye is coupled thereto. The resulting 3'- and/or 2'-amino- and thiol-modified nucleosides, nucleotides and oligonucleotides can then be used for the synthesis of complementary strands in the presence of a template strand or of oligonucleotides and for the detection of genetic material. They have the advantage that the fluorescent label need no longer be attached to the 5' end of the oligonucleotide or to the nucleobase, and thus need not be introduced during the chemical synthesis as in labeling techniques hitherto known, while the known and conventional methods have the disadvantage that only a few polymerases can be employed for the synthesis, the acceptance of the triphosphates by the polymerases diminishes and, moreover, a large substrate excess is necessary.
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- N-Heterocyclyl-N-cyano-N-(heterocyclythioalkyl)-guanidines
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Compounds of formula I and salts thereof which are orally pharmacologically active as inhibitors of gastric secretion are disclosed.
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- A Convenient Preparation of Anhydrous Alkali Metal Thiocarboxylates
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A series of alkali metal thiocarboxylates (1-5) were found to be readily obtained in high yields by the reaction of thiocarboxylic acids with metal hydrides (LiH, NaH, KH), and rubidium or caesium acetates, respectively.Their physical properties were disclosed. - Keywords: Lithium Thiocarboxylates, Sodium Thiocarboxylates, Potassium Thiocarboxylates, Rubidium Thiocarboxylates, Caesium Thiocarboxylates
- Kato, Shinzi,Oguri, Motohiro,Ishida, Masaru
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p. 1585 - 1590
(2007/10/02)
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- Antiarteriosclerotic N-(mercaptoacyl)-histidines
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This invention relates to the compound: N-(mercaptoacyl)-histidine represented by the following formula wherein n is 1 or 2, having activity as an antiarteriosclerosis agent, the intermediate thereof and a process for manufacture thereof. STR1
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