In this synthetic procedure, a seven-step protocol for the preparation of monosubstituted 3-bromo-1,2,4,5-tetrazine is presented. The procedure features efficient transformations and purification methods starting from commercially readily available materials affords title compound on gram scale with 13 % overall yield in reliable purity (>97 %). Detailed experimental procedures, supported by im...

Purpose: The [18F]-fluorodeoxyglucose ([18F]-FDG) is known to be one of the most used radio-pharmaceuticals for positron emission tomography. [18F]-FDG allows assessment glycolytic activity, which more enhanced in tumor cells than normal cells. It also heart and neurological diseases. aim our work follow possibility modifying develop an indirect radiofluorination procedure applicable under stan...

The development of fluorogenic reactions which lead to the formation of fluorescent products from two nonfluorescent starting materials is highly desirable, but challenging. Reported herein is a new concept of fluorescent product formation upon the inverse electron-demand Diels-Alder reaction of 1,2,4,5-tetrazines with particular trans-cyclooctene (TCO) isomers. In sharp contrast to known fluor...

The Click Activated Protodrugs Against Cancer (CAPAC) platform enables the activation of powerful cancer drugs at tumors. CAPAC utilizes a click chemistry reaction between tetrazine and trans-cyclooctene. activator, linked to tumor-targeting agent, protodrug leads targeted drug. Here, tumor targeting is achieved by intratumoral injection tetrazine-modified hyaluronate (SQL70) or infusion HER2-t...

Strain-promoted inverse electron-demand Diels-Alder cycloaddition (SPIEDAC) reactions between 1,2,4,5-tetrazines and strained dienophiles, such as bicyclononynes, are among the fastest bioorthogonal reactions. However, the synthesis of 1,2,4,5-tetrazines is complex and can involve volatile reagents. 1,2,4-Triazines also undergo cycloaddition reactions with acyclic and unstrained dienophiles at ...

Cycloaddition reactions involving tetrazines have proven to be powerful bioorthogonal tools for various applications. Conceivably, sequential and selective labeling using tetrazine-based reactions can be achieved by tuning the reaction rate. By varying the substituents on tetrazines, cycloaddition rate variations of over 200 fold have been achieved with the same dienophile. Upon coupling with d...