Identification of Lactam-Lactim Tautomers of Aromatic Heterocycles in Aqueous Solution Using 2D IR Spectroscopy.
Identification of Lactam-Lactim Tautomers of Aromatic Heterocycles in Aqueous Solution Using 2D IR Spectroscopy.
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DOI：
10.1021/jz301706a
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发表时间：
2012-10-24
期刊：
影响因子：
--
通讯作者：
Tokmakoff A
中科院分区：
文献类型：
--
作者：
Peng CS;Tokmakoff A
芳香杂环的互变异构性直接影响其化学性质和生物学功能，引起了人们的广泛关注。利用红外光谱（FTIR）、二维红外光谱（2D IR）和密度泛函理论（DFT）计算，研究了2-吡啶酮、6-氯-2-吡啶酮和4-嘧啶酮在D2O中的互变异构性。利用二维红外交叉峰图将6-氯-2-吡啶酮的乳互变异构体与内酰胺互变异构体分离，并观察到其数量随温度升高而增加。测定了6-氯-2-吡啶酮在室温下的平衡常数为2.1。同样，4-嘧啶酮的N1H和N3H内酰胺互变异构体也用二维红外光谱进行了鉴定。为了确定不同互变异构体的振动模式，我们用明确的水分子对这些化学物质进行了DFT计算，并建立了水合作用对振动频率和强度的影响。
The tautomerism of aromatic heterocycles is of great interest because it directly affects their chemical properties and biological function. The tautomerism of 2-pyridone, 6-chloro-2-pyridone, and 4-pyrimidinone have been examined in D2O using FTIR, two-dimensional IR (2D IR) spectroscopy and density functional theory (DFT) calculations. Using the 2D IR cross-peak patterns, the lactim tautomer of 6-chloro-2-pyridone was separated from the lactam tautomer, and its population was observed to increase with temperature. The equilibrium constant of [lac-tam]/[lactim] was determined to be 2.1 at room temperature for 6-chloro-2-pyridone. Similarly, the N1H and N3H lactam tautomers of 4-pyrimidinone were identified with 2D IR. To assign the vibrational modes of different tautomers, DFT calculations of these chemical species were performed with explicit water molecules, and the hydration effects on the vibrational frequencies and intensities were established.
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DOI：
10.1111/j.1742-4658.2009.06964.x
发表时间：
2009-05
期刊：
The FEBS journal
影响因子：
--
作者：
Nemeria NS;Chakraborty S;Balakrishnan A;Jordan F
通讯作者：
Jordan F
影响因子：
3.6
作者：
Llor, J;Muñoz, L
通讯作者：
Muñoz, L
影响因子：
2.9
作者：
Mata, Santiago;Cortijo, Vanessa;Blanco, Susana
通讯作者：
Blanco, Susana
影响因子：
15
作者：
Hass, Mathias A. S.;Hansen, D. Flemming;Kay, Lewis E.
通讯作者：
Kay, Lewis E.
影响因子：
64.8
作者：
HUNTER, WN;BROWN, T;KENNARD, O
通讯作者：
KENNARD, O