Sulfonated Hydroxyaryl-Tetrazines with Increased pK_a for Accelerated Bioorthogonal Click-to-Release Reactions in...

Area of Science:

• Bioorthogonal Chemistry
• Organic Chemistry
• Chemical Biology

Background:

• Tetrazine-mediated cleavage of trans-cyclooctene caged compounds is a versatile bioorthogonal reaction.
• Developing highly reactive tetrazines for efficient release from trans-cyclooctene linkers remains a challenge.

Purpose of the Study:

• To synthesize and characterize novel sulfo-tetrazines with enhanced reactivity.
• To demonstrate the utility of sulfo-tetrazines in activating caged molecules in biological systems.

Main Methods:

• Synthesis of sulfo-tetrazine derivatives featuring phenolic hydroxyl groups.
• Measurement of acidity constants (pK_a) to correlate with reactivity.
• Application of sulfo-tetrazines for activating fluorogenic compounds and prodrugs in living cells.

Main Results:

• Sulfo-tetrazines exhibit increased acidity constants, leading to accelerated elimination kinetics.
• Quantitative release of caged molecules was achieved within minutes.
• Demonstrated successful derivatization of sulfonate groups for further functionalization.
• Validated the activation of fluorogenic probes and prodrugs in living cells.

Conclusions:

• Sulfo-tetrazines represent a significant advancement in bioorthogonal chemistry, offering improved reactivity and versatility.
• These novel compounds facilitate rapid and complete uncaging, expanding possibilities for in vivo applications.
• The synthetic handle provided by sulfonate groups allows for tailored molecular design in bioorthogonal systems.