翻訳と辞書 Words near each other ・ Pseudo-spectral method ・ Pseudo-squeeze ・ Pseudo-Tertullian ・ Pseudo-top-level domain ・ Pseudo-transparency ・ Pseudo-uniform polyhedron ・ Pseudo-warm front ・ Pseudo-wire ・ Pseudo-Zernike polynomials ・ Pseudo-zero set ・ Pseudo.com ・ Pseudoacanthocereus ・ Pseudoacanthocereus brasiliensis ・ Pseudoacanthosis nigricans ・ Pseudoachondroplasia ・ Pseudoacid ・ Pseudoacontias ・ Pseudoakuammigine ・ Pseudoallergy ・ Pseudoalteromonadaceae ・ Pseudoalteromonas ・ Pseudoalteromonas agarivorans ・ Pseudoalteromonas aliena ・ Pseudoalteromonas antarctica ・ Pseudoalteromonas arctica ・ Pseudoalteromonas atlantica ・ Pseudoalteromonas aurantia ・ Pseudoalteromonas bacteriolytica ・ Pseudoalteromonas byunsanensis ・ Pseudoalteromonas carrageenovora Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Pseudoacid ： ウィキペディア英語版 Pseudoacid A Pseudoacid in Organic Chemistry is a cyclic oxocarboxylic acid. Most commonly, these form from aldehyde and keto carboxylic acids, and the cyclic forms are furanoid (5-ring with oxygen) or pyranoid (6-ring with oxygen). The original pseudoacid to be described as such (using the German "pseudosauren") was levulinic acid (4-oxopentanoic acid).〔1. Bredt, J., 1886. Ueber Acetyllävulinsäure und die Constitution der γ-Ketonsäuren. Annalen der chemie 236, 225– 240.〕 Unlike the parent (open-form) oxocarboxylic acid, the pseuodacid has a chiral center. The position of equilibrium in oxocarboxylic acids, toward the open form or the cyclic (pseuodacid) form, is influenced by a number of factors. In aliphatic 4- and 5-oxocarboxylic acids, intervening substituents assists in ring closure. Alkenes with the interacting groups substituted cis to each other also assists in ring closure. Aryl systems with the interacting groups substituted ortho to each other assists in ring closure. Other factors such as the gem-dialkyl effect (Thorpe-Ingold effect), electronic influences, and steric compression can also influence the open-cyclic equilibrium. Like carboxylic acids, pseuodacids have "pseudoacyl" derivatives. These include pseudoacyl halides, pseudoesters, endocyclic and exocyclic-N pseudoamides, and pseudoanhydrides. Like aldehydes and ketones, pseuodacids have "pseudocarbonyl" derivatives also. ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pseudoacid」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.