Vitamin B12 derivatives for orthogonal functionalization.

Area of Science:

• Medicinal Chemistry
• Organic Synthesis
• Bioconjugation Chemistry

Background:

• Vitamin B12 is a crucial biomolecule with potential therapeutic applications.
• Existing methods for modifying vitamin B12 are limited in scope and stability.
• Orthogonal conjugation strategies are needed for developing advanced drug delivery systems.

Purpose of the Study:

• To synthesize novel vitamin B12 derivatives.
• To achieve selective conjugation at the cobalt center and the 5'-hydroxyl group.
• To explore the utility of these derivatives as drug carriers.

Main Methods:

• Developed a reduction-free, direct alkynylation method for vitamin B12.
• Utilized acetylide formation at the cobalt center.
• Employed selective [1,3] dipolar azide-alkyne cycloadditions (AACs) and carbamate formation for functionalization.

Main Results:

• Achieved versatile synthesis of vitamin B12 derivatives.
• Formed highly stable cobalt-centered acetylides, resistant to heat and light.
• Demonstrated high-yielding functionalization via click chemistry (AAC).

Conclusions:

• The novel vitamin B12 derivatives are stable and versatile.
• The developed synthetic route enables orthogonal conjugation.
• These derivatives show significant promise as drug carriers.