2479-49-4
2479-49-4 結(jié)構(gòu)式
基本信息
3,3’,4,4’-二苯酮四酸
4,4’-羰基雙(1,2-苯二甲酸)
酮酸
4,4'-CARBONYLDIPHTHALIC ACID
Benzophenone-3,3',4,4'-tetracarboxylic acid
BENZOPHENONE TETRACARBOXYLIC ACID
BTA
2-Benzenedicarboxylicacid,4,4’-carbonylbis-1
3,3’,4,4’-Diphenylketonetetracarboxylicacid
4,4’-carbonylbis-2-benzenedicarboxylicacid
4,4'-Carbonylbis(1,2-benzenedicarboxylic acid)
4,4'-Carbonylbis(phthalic acid)
物理化學(xué)性質(zhì)
常見問(wèn)題列表
酮酸分為2種：α酮酸和β酮酸。
① α酮酸是羧基在阿爾法碳原子上的的酮酸，也就是酮基碳原子與羧基碳原子直接相連的酮酸。丙酮酸是最簡(jiǎn)單的α酮酸，丙酮酸可以隨酒精發(fā)酵的過(guò)程中分解為乙醛和二氧化碳。在酶的作用下也可以分解為乙酰輔酶A和二氧化硫。三羧酸循環(huán)中有一個(gè)類似的反應(yīng)。 在實(shí)驗(yàn)室里使用強(qiáng)硫酸可以瓦解-CO-COOH上比較弱的C-C鍵，丙酮酸比如可以在這個(gè)反應(yīng)中被分解為一氧化碳和醋酸。 另一個(gè)典型的反應(yīng)是轉(zhuǎn)氨基反應(yīng)，在這個(gè)反應(yīng)中一個(gè)α酮酸獲得一個(gè)氨基，同時(shí)一個(gè)谷氨酸失去一個(gè)氨基，而不釋放氨。通過(guò)這個(gè)反應(yīng)丙酮酸可以轉(zhuǎn)化為丙氨酸，草酰乙酸(它同時(shí)是一個(gè)α酮酸和β酮酸)轉(zhuǎn)化為天冬氨酸，a-酮戊二酸轉(zhuǎn)化為谷氨酸。
② β酮酸的羧基與酮基之間還隔著一個(gè)碳原子。β酮酸非常不穩(wěn)定，它會(huì)自動(dòng)脫羧，在細(xì)胞中這個(gè)過(guò)程通過(guò)催化劑作用發(fā)生。比如在糖異生（生物體將多種非糖物質(zhì)轉(zhuǎn)變成葡萄糖或糖原的過(guò)程）過(guò)程中草酰乙酸的脫羧。
The kinetics of the photooxidation of aromatic amino acids histidine (His), tyrosine (Tyr), and tryptophan (Trp) by Benzophenonetetracarboxylic acid has been investigated in aqueous solutions using time-resolved laser flash photolysis and time-resolved chemically induced dynamic nuclear polarization. The pH dependence of quenching rate constants is measured within a large pH range. The chemical reactivities of free His, Trp, and Tyr and of their acetylated derivatives, N-AcHis, N-AcTyr, and N-AcTrp, toward Benzophenonetetracarboxylic acid triplets are compared to reveal the influence of amino group charge on the oxidation of aromatic amino acids. Thus, it has been established that the presence of charged amino group changes oxidation rates by a significant factor; i.e., His with a positively charged amino group quenches the Benzophenonetetracarboxylic acid triplets 5 times more effectively than N-AcHis and His with a neutral amino group. The efficiency of quenching reaction between the Benzophenonetetracarboxylic acid triplets and Tyr and Trp with a positively charged amino group is about 3 times as high as that of both Tyr and Trp with a neutral amino group, N-AcTyr and N-AcTrp.