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51.
2-Methylthio-4-alkenoic esters prepared from 1-alkenes and ethyl methylsulfinylacetate are converted into α,β-unsaturated esters via hydrogenation, oxidation, and thermolysis. This method was applied to the synthesis of queen substance.  相似文献   
52.
A bisdehydro[14]annuleno[c]furan, an isoannelated diatropic annulene, has been synthesized. Cyclic glycol, a precursor of the annuleno[c]furan, could be converted into bisdehydro[14]annulene derivatives under mild acidic conditions.  相似文献   
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Tetrakisdehydro[14]annuleno[14]annulene consisting of ‘acetylene-cumulene’ bisdehydro[14]annulene and Sondheimer's bishydro[14]annulene has been synthesized. It was found that a strong diatropicity was observed in the ‘acetylene-cumulene’ bisdehydro[14]annulene moiety, whereas diatropicity of another bisdehydro[14]annulene moiety shows marked decrease comparable with that of napthobisdehydro[14]annulene synthesized by Sondheimer.  相似文献   
55.
Self-assembled monolayer (SAM) was successfully adsorbed on the AZ31 Mg alloy surface using oleic acid and stearic acid with various organic solvents, such as acetone, ethanol, and hexane. The surface monolayers were characterized using contact angle measurements, X-ray photoelectron spectroscopy (XPS) and anodic polarization test. It was shown that the higher contact angle and the best anti-corrosion property were obtained with treatment in oleic acid with ethanol solution.  相似文献   
56.
Using aqueous–organic interface (water–oleic acid) reduction of Cu2+ by ascorbic acid, hydrophobic copper monolayer and copper particles have been prepared and characterized. The resultant monolayer could be transferred from the interface onto solid substrate or be dissolved to yield an organosol and copper nanoparticles.  相似文献   
57.
Fused cyclobutanone derivatives have been utilized as intermediates in a variety of synthetic schemes.1) We are investigating the synthesis and ring opening reactions of cyclobutanones fused to indoles, benzo[b]furans, and benzo[b]-thiophenes, in part with the hope of discovering a novel method for introduction of two carbon atoms to such heteroaromatic systems. In this communication the synthesis and Beckmann fission2) of the cyclobutanone derivatives fused to 1-benzoyl-indoles and benzo[b]thiophene are described. This provides a new entry into indole-2-acetonitriles3) and benzo[b]thiophene-2-acetonitrile.4)  相似文献   
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Human being have been using inorganic arsenic for a long time. Many reports on arsenic poisoning have been published: eg case reports, examination reports, post mortem reports, and epidemiological studies. Several aspects and features of arsenic poisoning are discussed in this report. Methods of inferring arsenic-related disease, disease classification according to acute or chronic criteria, exposure route, interaction, confounding factors, and the oxidation state of arsenic are all discussed. The effects of arsenic are classified into skin, respiratory system, gastrointestinal tract, liver, cardiovascular system, nervous system, and bone marrow effects. Carcinogenicity is an important chronic effect of arsenic poisoning, so special attention is paid to it in this review. In Japan, there have been many incidents of arsenic poisoning. In this review, we often use data from these cases, such as the Morinaga powdered-milk poisoning case, the Ube soy-sauce poisoning case, the Toroku mine incident, and the Nakajo well-water poisoning case. We emphasize here the necessity of planning follow-up studies and total health care for patients exposed to arsenic.  相似文献   
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