The 1,2,4,5-tetrazines are known to undergo the Strain-Promoted Inverse Electron-Demand Diels-Alder Reaction (SPIEDAC) with strained C-C multiple bonds and are gaining attention as third-generation click reactions. This is a novel method that overcomes the limitations of traditional click reactions, enabling more efficient and specific bonding. Additionally, this reaction meets the criteria for bioorthogonal reactions (fast, selective, biocompatible, catalyst-free) and is being recognized as an innovative technology across various fields such as protein labeling, imaging, and pharmaceutical development.

In recent years, there has been active research aimed at breaking the planarity of pharmacologically active molecules to improve their solubility and in vivo behavior. This approach involves replacing the benzene ring with bioisosteres. We offer the custom synthesis of analogues and derivatives, as well as scale-up production of these building blocks.

We are proud to present the three component reaction with the Hosomi-Sakurai allylation reaction using allyl(trimethyl)silane [A0729].

TCI introduces the modification reaction of cysteine methyl ester by using the cyclopropenone derivative [C3904]. Cyclopropenone derivatives selectively react with the N-terminal cysteine residue.