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切换结合是通过N-甲基化完全逆转胺cis-trans (Z-E) 偏好的主要因素

Junjun Huang^1,2, Luying Chen^3,2, Hirotaka Ikeda²

¹The Fifth Affiliated Hospital, Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology, The NMPA and State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou 511436, China.

The Journal of organic chemistry

|April 1, 2025

概括

N-甲基化改变了胺构成,有利于甲化物中的cis形式. 这是由于电子结合的再平衡而发生的,而不仅仅是硬质障碍,影响了分子设计.

科学领域:

有机化学有机化学
计算化学的计算化学
分子结构分子结构

背景情况:

N-甲基化显著影响胺,特别是甲化物中cis-trans (Z-E) 异构体的偏好.
虽然NH-甲化物更喜欢转 (E) 形状,但N-甲基化会导致转向cis (Z) 形状.
这种形状转换通常归因于硬质因素,但可能涉及其他机制.

研究的目的:

调查驱动N-甲基化甲基化物中cis-trans (Z-E) 偏好转变的潜在机制.
探索电子扰动和键轨道相互作用在确定胺基构造中的作用.
通过基于对联的替代解释,挑战当前的固体障碍假设.

主要方法:

雇佣债券模型分析 (BMA) 来研究结构偏好.
在电子干扰下评估 cis-trans (Z-E) 偏好的稳定性 (电子捐赠/提取组).
分析了由于N-甲基化而导致的结合途径的变化.

主要成果:

N-甲基化重新平衡了甲基化物内的电子结合.
由于氨酸和氨酸的结合,NH-甲化物有利于转变 (E) 形状.
由于增强的-碳结合,N-甲基二化物有利于cis (Z) 形状.

结论:

在N-甲基甲基化物中,构造性切换主要是由改变的电子结合驱动的,而不是仅仅是固态阻碍.
了解这些结合再平衡效应对于涉及N-甲基化胺的分子设计至关重要.
债券模型分析提供了对有机分子结构偏好的电子起源的洞察.

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