Articles by Topic "Amide bond construction"

1. Selective Acylation of Less Reactive Amines in Complex Substrates: Strategies for N/O and N/N Selectivity Control This article draws on the work of Li et al. on the TCFH/catalytic Oxyma system and transient imine protection, and summarizes design strateg
   posted this at Jun 16, 2026

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   This article draws on the work of Li et al. on the TCFH/catalytic Oxyma system and transient imine protection, and summarizes design strategies for the selective acylation of less reactive amines in complex substrates. The discussion below focuses on identifying competing reactive sites, ...
2. Experimental Judgment for TFPN in Carboxylic Acid Activation: Suitable Scenarios, Intermediate Distribution, and Nucleophile Compatibility
   posted this at Apr 22, 2026

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   TFPN [tetrafluorophthalonitrile, 3,4,5,6-tetrafluorophthalonitrile] has in recent years been used for amide bond and peptide bond formation under carboxylic acid activation conditions. Published studies have shown that this route can be applied to sterically hindered substrates and difficult ...
3. Ynamide Coupling Reagents: From Low-Epimerization Activation Pathways to More Practically Usable N→C Inverse Peptide Synthesis
   posted this at Apr 7, 2026

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   In peptide synthesis, what is often truly difficult to control is not whether an amide bond can be formed, but rather how to minimize epimerization at the α-stereogenic center of the activated carboxylic acid component during activation and the subsequent bond-forming process. This issue is ...
4. Low Racemization in Peptide Synthesis Is Not Just About Reagent Choice: Stereochemical Risk During the Activation Stage and Practical Strategies for Experimental Control
   posted this at Mar 30, 2026

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   “Racemization” in peptide synthesis is often discussed as if it were mainly a question of whether one coupling reagent is better than another. From the standpoint of reaction chemistry, however, what deserves greater caution is the period after the carboxylic acid has been activated. In many ...
5. The Positioning of TBTU in Practice: Racemization Risk, Extended Uses, and Selection Criteria
   posted this at Mar 29, 2026

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   TBTU [O-(benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate] has long been one of the most commonly used coupling reagents for carboxylic acid activation and amide bond formation, and has been widely employed in both solution-phase amidation and solid-phase peptide synthesis ...
6. From “Reduction First, Then Acylation” to “Direct Amidation”: An Unconventional Route to Amide Bond Formation from Nitro and Nitroso Substrates with α-Keto Carboxylic Acids
   posted this at Mar 23, 2026

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   The most familiar route from nitro compounds to amides is usually to first reduce the nitro group to an amine, and then react that amine with a carboxylic acid derivative or an activated carboxylic acid system. This route is mature, reliable, and remains the most common choice in both laboratory ...
7. A New Balance in Coupling Reagents: How DMT-TU Balances Reactivity, Racemization Control, and Thermal Hazard
   posted this at Mar 23, 2026

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   Amide bond formation is one of the most common fundamental reactions in organic synthesis, medicinal chemistry, and peptide chemistry. For a long time, when evaluating coupling reagents, the first concerns were usually whether the reaction was fast enough, whether the yield was high enough, and ...
8. TCFH–NMI Amidation in Highly Aqueous Media: Research Value, Methodological Understanding, and Experimental Insights
   posted this at Mar 22, 2026

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   Amide bond formation is one of the most common fundamental transformations in the synthesis of drug molecules, natural products, and functional molecules. In efforts to improve amidation reactions, researchers are concerned not only with whether a bond can be formed, but also with whether the ...