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Published on: July 17, 2020
1,9-Dialkoxyanthracene as a (1)O2-sensitive linker.
Dumitru Arian1, Larisa Kovbasyuk, Andriy Mokhir
1Institute of Inorganic Chemistry, Ruprecht-Karls-University of Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
Journal of the American Chemical Society
|February 25, 2011
Summary
Researchers developed a novel singlet oxygen (¹O₂) sensitive linker for creating advanced molecular tools. This linker enables rapid, high-yield reactions, facilitating the development of new probes and caged compounds.
Area of Science:
- Organic Chemistry
- Biochemistry
- Molecular Biology
Background:
- Singlet oxygen (¹O₂) plays crucial roles in biological processes and photodynamic therapy.
- Development of precise tools for ¹O₂ detection and manipulation is essential for biological research and therapeutic applications.
Purpose of the Study:
- To design and synthesize a novel (1)O(2)-sensitive linker based on a 9,10-dialkoxyanthracene structure.
- To develop a fluorogenic probe for monitoring (1)O(2) in live mammalian cells.
- To create visible-light-activated "caged" oligodeoxyribonucleotides for targeted nucleic acid delivery.
Main Methods:
- Synthesis of a phosphoramidite building block incorporating the (1)O(2)-sensitive linker.
- Coupling the linker to various molecular fragments, including nucleosides, fluorescent dyes, and a cholesteryl derivative.
- Preparation of a fluorogenic probe by conjugating tetrachlorofluorescein and tetramethylrhodamine via the linker.
- Construction of "caged" oligodeoxyribonucleotides with the linker in a blocker strand.
Main Results:
- The (1)O(2)-sensitive linker demonstrates rapid and high-yielding cleavage upon exposure to (1)O(2).
- The fluorogenic probe exhibits quenched fluorescence that is restored upon linker cleavage by (1)O(2), correlating with ¹O₂ concentration.
- Visible-light-activated "caged" oligodeoxyribonucleotides are efficiently uncaged, releasing the active strand with high yield.
Conclusions:
- The developed (1)O(2)-sensitive linker is a versatile building block for creating sensitive probes and efficient caged compounds.
- The fluorogenic probe offers a reliable method for real-time monitoring of (1)O(2) in biological systems.
- The "caged" oligodeoxyribonucleotides provide a promising platform for light-activated gene targeting and therapeutic applications.
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Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...