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Updated: Jan 5, 2026

Determination of the Gas-phase Acidities of Oligopeptides
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Determination of the Gas-phase Acidities of Oligopeptides

Published on: June 24, 2013

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使用图形卷积神经网络的pKa值的快速和准确预测

Rafał Roszak1,2, Wiktor Beker1,2, Karol Molga1

  • 1Institute of Organic Chemistry , Polish Academy of Sciences , ul. Kasprzaka 44/52 , 01-224 Warsaw , Poland.

Journal of the American Chemical Society
|October 22, 2019
PubMed
概括

预测有机分子的酸性对于合成计划至关重要. 图形卷积神经网络 (GCNN) 准确地估计非水性溶剂中的C-H酸度,帮助化学家预测反应.

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Basicity of Aliphatic Amines01:21

Basicity of Aliphatic Amines

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.
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This lesson delves into a critical aspect of the relative strengths of acids and bases. The strength of an acid is evaluated by the acid dissociation into its conjugate base and a hydronium ion in water. The complete dissociation of a strong acid is confirmed with a very high concentration of hydronium ions. As a result, an incomplete dissociation process affirms a weak acid. Therefore, the equilibrium is in the forward direction for strong acids and backward for weak acids in these reactions.
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Acidity of Carboxylic Acids

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IR and UV–Vis Spectroscopy of Carboxylic Acids

In IR spectroscopy of carboxylic acids, the C=O bond shows a characteristic band between 1710 and 1760 cm⁻¹, and the O–H bond exhibits a broad band between 2500 and 3300 cm⁻¹.
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