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1.
The chemiluminescence (CL) intensities of various indole derivatives substituted with a glyoxylyl group at the 3-position and a hydroxyl group at the 5-position of the indole ring were compared upon the addition of H2O2 in alkaline media. The CL intensities of 3-indoleglyoxylyl chloride, 3-indoleglyoxylic acid, 5-hydroxyindole and 5-benzyloxyindole in CH3CN were 5.9-, 48-, 5.9- and 3.3-fold stronger than that of 3-methylindole. A lasting CL of 3-indoleglyoxylyl chloride was found. Under appropriate conditions, the CL emission reached a maximum within 10 min after the addition of H2O2 in the presence of NaOH, and the intensity was retained for 25 min. One of the final products via the CL reaction of 3-indoleglyoxylyl chloride was indole-3-carboxylic acid. 3-Indoleglyoxylyl chloride emitted light by decompositions via both dioxetane and dioxetanedione. An enhancement effect of beta-cyclodextrin and bovine serum albumin on the CL of 3-indoleglyoxylyl chloride was also found. 相似文献
2.
Hiroshi Yamauchi Keiko Takahashi Mari Mashiko Juichiro Saitoh Yukio Yamamura 《应用有机金属化学》1992,6(4):383-388
We calculated the intake of each chemical species of dietary arsenic by typical Japanese, and determined urinary and blood levels of each chemical species of arsenic. The mean total arsenic intake by 35 volunteers was 195±235 (15.8-1039) μg As day?1, composed of 76% trimethylated arsenic (TMA), 17.3% inorganic arsenic (Asi), 5.8% dimethylated arsenic (DMA), and 0.8% monomethylated arsenic (MA): the intake of TMA was the largest of all the measured species. Intake of Asi characteristically and invariably occurred in each meal. Of the intake of Asi, 45-75% was methylated in vivo to form MA and DMA, and excreted in these forms into urine. The mean measured urinary total arsenic level in 56 healthy volunteers was 129±92.0 μg As dm?3, composed of 64.6% TMA, 26.7% DMA, 6.7% Asi and 2.2% MA. The mean blood total arsenic level in the 56 volunteers was 0.73±0.57 μg dl?1, composed of 73% TMA, 14% DMA and 9.6% Asi. The urinary TMA levels proved to be significantly correlated with the whole-blood TMA levels (r = 0.376; P<0.01). 相似文献
3.
The relationship between the four components, (1) fluorescence intensity, (2) arsenic concentration, (3) pH and (4) total dissolved solids, (TDS) measured in well waters from areas in Taiwan where blackfoot disease (BFD) is endemic was studied, as well as the relationships between the four degrees of BFD and each of the above four symptomatic components, in order to evaluate the etiological factors of BFD more progressively. The following 95% confidence intervals were obtained in well water samples (n = 1189): fluorescence intensity, 26.837–32.570; arsenic concentration, 0.103–0.127 mg dm?3; pH, 7.466–7.519; and TDS 733.063–801.647 mg dm?3. Fluorescence intensities of the four degrees of BFD were not all the same (F = 64.54, P < 0.001), and nor were arsenic concentrations (F = 72.03, P < 0.001), pH values (F = 7.30, P < 0.001), nor TDS values (F = 10.76, P < 0.001). In addition, multiple comparisons indicate that the higher the epidemical degree, the higher the fluorescence intensities, arsenic concentrations and pH values become; however, such a relationship is not found for TDS values. Moreover, the fluorescence intensities have positive linear correlations with arsenic concentrations (r = 0.49, P < 0.001), pH (r = 0.25, P < 0.001), and TDS (r = 0.18, P < 0.001), as do the arsenic concentrations with pH (r = 0.22, P < 0.001). Of the four epidemical degree groups, pairs are not significantly different from one another in correlation coefficients between fluorescence intensity and arsenic concentration, which implies a steady relationship between fluorescent compounds and arsenic. We conclude that fluorescent compounds in well water, as possible etiological factors of BFD, are closely related to arsenic along with pH and TDS values in the areas where BFD is endemic. In addition, we infer that a complex is formed by fluorescent compounds, arsenic and other metals. 相似文献
4.
5.
In the crystal of the title compound, the quinone fragment of the host (1) participates in weak D-A interactions with a neighboring naphthalene moiety of 1 and with the guest molecule via fairly short intermolecular face-to-face contacts. An intermolecular electrostatic interaction between a quinone-oxygen atom and a neighboring quinone ring is suggested by short O...C contacts. There exist several C-H...O hydrogen bonds, one of which seems to contribute to the formation of a centrosymmetric dimer of 1. 相似文献
6.
Six alkaloids have been isolated from the fruits of the plant Daphniphyllaceae. Two of them are new alkaloids, namely methyl homodaphniphyllate (1) and daphnilactone-B (2). The structure of the former was deduced by chemical transformation from daphniphylline (3). The structure of daphnilactone-B was estimated by the exhaustive spectral analysis as well as by chemical evidences, and finally determined by an X-ray crystallographic analysis of the free base. 相似文献
7.
From a biogenetic point of view, a great variety of related alkaloids isolated from the plant Daphniphyllaceae are related to one another by bond formation or fission. Thus, daphnialcohol acetate (6), a derivative of the degradation products of daphniphylline (1), was subjected to von Braun degradation followed by acid-catalyzed recyclization to give an isomer (8) of daphnialcohol, which has a new type of nitrogen heterocyclic skeleton. Furthermore, daphnilactone-B (3) was converted into a daphniphylline-type compound (19) via a plausible intermediate (21). 相似文献
8.
The structures of several clerodane-type diterpenes [solidagolactones II (elongatolide C), III, IV (elongatolide A), V, VI (elongatolide D), elongatolide B, and elongatolide E] have been revised , all of which are -clerodanes. 相似文献
9.
10.