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81.
The ligands in [Cu(C19H27NPS2)2] adopt an S,S′‐chelation mode leading to an S4 donor set which defines a square‐planar geometry about the Cu atom, which lies on an inversion centre.  相似文献   
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84.
N-Alkylated polyhydrazides containing 1,3,4-oxadiazole linkages in them were prepared by solution polycondensation of dicarboxylic acid diesters with hydrazine in fuming sulfuric acid or polyphosphoric acid. Their preparation, characterization, and some physical properties are described.  相似文献   
85.
The first dipalladium μ-PPh(3) complex (1) was obtained by the facile loss of two CH(3)CN ligands from [Pd(2)(PPh(3))(2)(CH(3)CN)(4)](PF(6))(2) in CH(2)Cl(2). Coupling of p-tolylacetylene (p-TolC identical withCH) with 1 or its precusor afforded the μ-butenediylidene complex 2, treatment of which with CH(3)CN resulted in PPh(3) migration to give 3.  相似文献   
86.
Since azido derivatives of 1,5-benzothiazepine Ca antagonist available for photoaffinity labeling are required for further studies of voltage-sensitive Ca channels, we synthesized 3-(p-azidobenzoyloxydeacetyl)- and 3-(4-azidobutyryloxydeacetyl)-diltiazem, and studied their pharmacological properties. Both azido compounds showed similar relaxing actions to diltiazem in K(+)-depolarized dog arteries. They also showed a similar increasing action to diltiazem, but less potent, on the coronary and vertebral blood flow in the anesthetized dog. Moreover, their negative inotropic effects in the guinea pig papillary muscle were similar to or slightly more potent than that of diltiazem under physiological conditions, but were less potent when studied in K+ depolarizing solution. A radioligand binding study in rat skeletal muscle microsomes revealed that the azido derivatives had similar properties to diltiazem, but the nonspecific binding of 3-(p-azidobenzoyloxydeacetyl)-diltiazem was too high to allow estimation of its KD and Bmax values. In conclusion, we synthesized azido derivatives of diltiazem which were considered to share a common binding site on the voltage-dependent Ca channel with diltiazem in skeletal muscle microsomes and in vascular smooth muscle.  相似文献   
87.
The reactions of β-keto sulfoxide, β-keto sulfones, or β-keto phosphinate with 1,1-disubstituted ethenes in the presence of manganese(III) acetate and molecular oxygen yielded 4-phenylsulfinyl-, 4-phenylsulfonyl-, or 4-phosphinoyl-1,2-dioxan-3-ols 3 in moderate-to-good yields. m-Chloroperbenzoic acid oxidation of 4-phenylsulfinyl-1,2-dioxan-3-ols gave the corresponding 4-phenylsulfonyl derivatives. The temperature dependence of the reactions was observed and the stereochemistry of the 1,2-dioxan-3-ols are discussed.  相似文献   
88.
N-Methylated polyhydrazides were prepared from methylated hydrazines and terephthalic acid or dimethyl terephthalate, and from terephthalic acid, hydrazine sulfate, and dimethyl sulfate by the solution polycondensation method in fuming sulfuric acid or polyphosphoric acid.  相似文献   
89.
The chemical synthesis of 13C-labeled mannose and fucose is important for the preparation of molecular probes used in the conformational study of the oligosaccharide portions of glycoproteins. A new method for the synthesis of the title [1-13C]-labeled compounds via the corresponding olefin compounds, which are in turn derived from d-mannitol or l-arabinose by efficient introduction of 13C, by the Wittig reaction using Ph3P13CH3I and n-BuLi, is described. The introduction of 13CH3I to produce the [1-13C]- and [6-13C]-labeled compounds was accomplished in 62%, 56%, and 71% yields, respectively. All mannose and fucose protons, from H-1 to H-6, were observed by the HMQC-TOCSY technique using 1:1 mixtures of [1-13C]- and [6-13C]-labeled compounds.  相似文献   
90.
Increase in the sensitivity of an immunosensor or biosensor requires the immobilization of a large amount of proteins. Good materials must be developed for this protein adsorption. Allylamine thin film was formed on a flat silver plate by plasma polymerization; this plate is referred to as Ag(ALAM). Ag(ALAM) films were characterized by SEM, FT–IR and ESCA. Investigations on adsorption and desorption of F(ab')2 anti-human IgG (hIgG) on to Ag and Ag(ALAM) revealed the following: (1) The adsorption isotherm of F(ab')2 anti-hIgG on to AG(ALAM) or Ag was of a Langmuir type. The binding constant (Kb) and saturation binding (Ab) for this protein on to Ag(ALAM) were 8.93 l/mol and 181.8 nmol/m2, respectively, and for Ag, were 7.71 l/mole and 87.9 nmol/m2. (2) The extent of desorption of labeled F(ab')2 anti-hIgG absorbed on the two plates was the same. (3) Ag(ALAM) and Ag were used as solid phases in a two-site immunoradiometric assay of human serum IgG. The dose-response on AG(ALAM) occurred at lower concentration, and was of greater magnitude than that on Ag.  相似文献   
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