2-(5-Norbornene-2,3-dicarboximido)-1,1,3,3-tetramethyluronium Tetrafluoroborate [Coupling Reagent for Peptide] TCI N0634

2-(5-Norbornene-2,3-dicarboximido)-1,1,3,3-tetramethyluronium Tetrafluoroborate from TCI, commonly abbreviated as TNTU, is a uronium salt coupling reagent for peptide chemistry. It activates the carboxyl group of amino acids and other carboxylic acids so that they react readily with amines to form amide bonds. The amide bond is the backbone of every peptide and of many pharmaceutical molecules. In the laboratory, TNTU is one of the main tools chemists use to join building blocks reliably when making peptides and amide-containing compounds.

TNTU belongs to the same family of uronium reagents as TBTU and HBTU. Unlike those reagents, it uses an N-hydroxy-5-norbornene-2,3-dicarboximide (HONB) framework as its activating group instead of a benzotriazole derivative. Chemists choose it because it converts carboxylic acids directly into HONB active esters. These esters have long been known in peptide synthesis as intermediates that are reactive but still reasonably controlled. Under suitable conditions, this helps suppress racemization of chiral amino acids. TNTU is a solid tetrafluoroborate salt, so it is easy to weigh and fits standard protocols that use a tertiary amine base.

In Indonesia, TNTU is relevant to university research groups, pharmaceutical and biotechnology development laboratories, and institutions working on synthetic peptides or small-molecule drug candidates. The reagent works in both solution-phase and solid-phase peptide synthesis, as well as in general amide formation in organic chemistry. This makes it a practical choice for laboratories that need one coupling reagent for several synthetic tasks. It suits teaching, method development and routine preparative work alike, whenever a reliable amide bond is needed.

• Solid-phase peptide synthesis: TNTU activates protected amino acids as HONB active esters, which lets resin-bound peptide chains grow step by step through controlled amide bond formation.
• Solution-phase peptide synthesis: Its solid, easily weighed salt form and compatibility with tertiary amine bases make it convenient for coupling peptide fragments and amino acids in solution.
• Racemization-sensitive couplings: The controlled reactivity of HONB active esters helps suppress racemization of chiral amino acids under appropriate conditions, which protects the stereochemical integrity of the product.
• General amide formation in organic synthesis: Beyond peptides, TNTU converts many carboxylic acids into active esters that react readily with amines, which is useful for building amide-containing target molecules.
• Pharmaceutical and medicinal chemistry research: The amide bond is common in drug molecules, so TNTU helps research laboratories prepare candidate compounds and intermediates that need dependable amide coupling steps.

Store TNTU in its original, tightly sealed container in a cool, dry and well-ventilated area, away from moisture, heat and incompatible substances. Coupling reagents of this type can lose activity if exposed to humidity. Reseal the container promptly after each use, and consider a desiccator for opened packs. Handle the reagent in a fume hood and wear appropriate personal protective equipment, including gloves, safety glasses and a lab coat. Avoid breathing dust and avoid contact with skin and eyes. Always check the TCI label and Safety Data Sheet for specific storage conditions, hazard information and disposal requirements.

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