Collection: Active Esters, Additives [Coupling Reagents]

Active Esters, Additives [Coupling Reagents] — contains active esters and additives such as tosylimidazole, trifluoromethylbenzoic anhydride, 2,4,6-trichlorobenzoyl chloride, and pentafluorophenyl carbonate, which activate carboxylic groups for the formation of amide or ester bonds. This category also includes brominated pyridinium salts that act as alternative activators in condensation reactions.

Active ester and additive reagents are widely used in peptide synthesis and amide bond formation, where the carboxylic group is activated first before reacting with an amine so that the coupling result is cleaner and more efficient. Fluorinated aryl anhydrides and benzoyl chloride derivatives are commonly chosen for Yamaguchi esterification in macrolide synthesis, while brominated pyridinium salts are used as alternative activators when conventional coupling reagents are less effective.

Example products in this collection: TCI T1985 2232-08-8 1-(p-Toluenesulfonyl)imidazole, TCI C0178 543-27-1 Isobutyl Chloroformate, TCI T1593 25753-16-6 4-Trifluoromethylbenzoic Anhydride, TCI C0903 14338-32-0 2-Chloro-1-methylpyridinium Iodide, TCI T1413 4136-95-2 2,4,6-Trichlorobenzoyl Chloride, TCI C0906 7403-46-5 2-Chloro-1-methylpyridinium p-Toluenesulfonate, TCI B3604 59483-84-0 Bis(pentafluorophenyl) Carbonate, TCI C1077 4457-32-3 4-Nitrobenzyl Chloroformate.

Choose based on the reactivity and selectivity of the activating group you need, the compound's sensitivity to air humidity, and solvent compatibility, so that carboxylic acid activation proceeds cleanly without side effects. All products are genuine Tokyo Chemical Industry (TCI) Japan products, with purity, packaging, and storage conditions listed on each item's page.

Other categories at the same level under Coupling [Synthetic Reagents], often used together in one laboratory workflow:

• Peptide Coupling Agents
• Phosphonium Salts, Uronium Salts, Formamidinium Salts [Coupling Reagents]
• Coupling Reagents (Other)
• Triflate Formation [Coupling Reagents]
• Carbodiimides [Coupling Reagents]
• Phosgene Derivatives [Coupling Reagents]

Back to Coupling [Synthetic Reagents]. For large-volume procurement, special packaging, or specific grades, contact the AMI Scientific team — official distributor of TCI Japan in Indonesia — for stock availability and lead time checks directly from Japan.