在初级氨基和氨基线的计算pKb确定中的新见解
Silvia Pezzola1, Mariano Venanzi1, Valeria Conte1
1Department of Chemical Science and Technologies, University of Rome Tor Vergata, Address Via della Ricerca Scientifica snc, 00133, Roma.
概括
一种新的计算方法准确地预测了初级氨基的酸解离常数 (pKb). 这种可靠,易于使用的方法将以前的pKa预测成功扩展到基本性计算.
科学领域:
- 计算化学的计算化学
- 物理有机化学 有机化学
- 药物发现 药物发现 药物发现
背景情况:
- 确立了酸解离常数 (pKa) 的准确预测.
- 缺乏可靠的基度 (pKb) 预测的in silico方法.
- 现有的pKa预测方法对pKb的性能不佳.
研究的目的:
- 开发和验证可靠的计算方法来预测初级氨基的pKb.
- 为了适应以前成功的pKa预测策略来确定pKb.
- 评估不同计算模型和解决方法的性能.
主要方法:
- 利用基于直接方法进行pKb预测的"易于使用的方法".
- 对比了CAM-B3LYP,WB97XD和B3PW91的功能.
- 采用基于密度 (SMD) 的溶解模型和两种显式水分子的极化连续模型 (PCM).
- 分析了溶剂可访问表面 (SAS) 和电子电位图 (EPM).
主要成果:
- 该CAM-B3LYP/SMD/2H2O方法证明了对pKb预测的特殊可靠性.
- 实现了低于0.3.3的最小平均误差 (MAE).
- CAM-B3LYP和WB97XD产生了不同的SAS和EPM,突出了模型的灵敏度.
- 该方法显示了原始胺和氨酸中的各种替代物的一致输出.
结论:
- 经过验证的CAM-B3LYP/SMD/2H2O方法提供了一种可靠且易于使用的工具,用于对初级胺和氨酸的pKb预测.
- 这扩展了该方法的已证明可靠性,从pKa计算到pKb计算.
- 这些发现加强了计算策略的可靠性,使其在化学和制药研究中得到更广泛的应用.
相关概念视频
Basicity of Aliphatic Amines
5.8K
Amines can behave as Brønsted–Lowry bases by accepting a proton from the acid to form corresponding conjugate acids. Due to a lone pair of nonbonding electrons, aliphatic amines can also act as Lewis bases by forming a covalent bond with an electrophile.
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates...
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates...
5.8K
Basicity of Heterocyclic Aromatic Amines
6.0K
Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).
6.0K
Basicity of Aromatic Amines
7.1K
The basicity of aromatic amines is much weaker than that of aliphatic amines due to the involvement of the lone pair of electrons over the N atom in resonance with the aryl rings. Generally, the electron-donating ability of any substituents on the aryl ring of aromatic amines increases the basicity of the amine by increasing electron density, and hence the availability of lone pair on the nitrogen. On the other hand, electron-withdrawing functional groups on the aryl ring of amines decrease the...
7.1K
Nomenclature of Primary Amines
3.4K
Primary, secondary, and tertiary amines are compounds consisting of one, two, and three alkyl groups connected to the amino group (–NH2), respectively. As depicted in Figure 1, the common name of the primary amines is obtained by adding the suffix -amine to the alkyl substituent attached to the amino group as the corresponding alkylamine.
3.4K
Preparation of Amines: Reductive Amination of Aldehydes and Ketones
2.8K
Carbonyl compounds and primary amines undergo reductive amination first to produce imines, followed by secondary amines in the same reaction mixture, using selective reducing agents like sodium cyanoborohydride or sodium triacetoxyborohydride. Reductive amination produces different degrees of substitution of amines depending on the starting amine substrate.
2.8K
Nomenclature of Aryl and Heterocyclic Amines
2.4K
The simplest aromatic amine is phenylamine, which contains an –NH2 functionality directly attached to an aromatic ring. The name aniline is designated for this skeleton. As shown in Figure 1, the common names of the functionalized anilines involve prefixes ortho-, meta-, and para- to indicate the substitution position. Different functionalized aniline derivatives also have notable trivial names.
2.4K


