Fluorescence Quenchers for Hydrazone and Oxime Orthogonal Bioconjugation
摘要:
We describe the synthesis and properties of new fluorescence quenchers containing aldehyde, hydrazine, and aminooxy groups, allowing convenient bioconjugation as oximes or hydrazones. Conjugation to oligonucleotides proceeded in high yield with aniline as catalyst. Kinetics studies of conjugation show that, under optimal conditions, a hydrazine or aminooxy quencher can react with aldehyde-modified DNA to form a stable hydrazone or oxime adduct in as little as five minutes. The resulting quencher-containing DNAs were assessed for their ability to quench the emission of fluorescein in labeled complements and compared to the commercially available dabcyl and Black Hole Quencher 2 (BHQ2), which were conjugated as phosphoramidites. Results show that the new quenchers possess slightly different absorbance properties compared to dabcyl and are as efficient as the commercial quenchers in quenching fluorescein emission. Hydrazone-based quenchers were further successfully incorporated into molecular beacons and shown to give high signal to background ratios in single nucleotide polymorphism detection in vitro. Finally, aminooxy and hydrazine quenchers were applied to quenching of an aldehyde-containing fluorophore associated with living cells, demonstrating cellular quenching within one hour.
[reaction: see text] The addition of aryl- and heteroarylboronic acids to azocompounds is described. Copper salt catalysis was necessary to perform the reaction under mild conditions and high yields. Excellent regioselectivity was observed in addition to unsymmetricalazocompounds.
Copper Salt Catalyzed Coupling of Organobismuth Reagents and Azo Compounds
作者:Uno Mäeorg、Olga Tšubrik、Ksenija Kisseljova
DOI:10.1055/s-2006-950408
日期:2006.9
A new copper salt catalyzed C-N coupling is described. This smooth reaction between azo compounds and organobismuth reagents provides efficient and highly regioselective access to Boc-protected aryl hydrazines. The yields under optimized conditions are mostly excellent and the synthetic procedure is robust and simple.
Aerobic Oxidation of Alkyl 2-Phenylhydrazinecarboxylates Catalyzed by CuCl and DMAP
作者:Min Hye Kim、Jinho Kim
DOI:10.1021/acs.joc.7b03119
日期:2018.2.2
various fruitful organic reactions such as a catalytic Mitsunobu reaction were reported by virtue of alkyl 2-phenylazocarboxylates, however, the synthesis of alkyl 2-phenylazocarboxylates largely depended on the stoichiometric use of toxic oxidants. In this manuscript, an environment-friendly aerobic oxidative transformation of alkyl 2-phenylhydrazinecarboxylates to alkyl 2-phenylazocarboxylates is
Fluorescence Quenchers for Hydrazone and Oxime Orthogonal Bioconjugation
作者:Pete Crisalli、Armando R. Hernández、Eric T. Kool
DOI:10.1021/bc300344b
日期:2012.9.19
We describe the synthesis and properties of new fluorescence quenchers containing aldehyde, hydrazine, and aminooxy groups, allowing convenient bioconjugation as oximes or hydrazones. Conjugation to oligonucleotides proceeded in high yield with aniline as catalyst. Kinetics studies of conjugation show that, under optimal conditions, a hydrazine or aminooxy quencher can react with aldehyde-modified DNA to form a stable hydrazone or oxime adduct in as little as five minutes. The resulting quencher-containing DNAs were assessed for their ability to quench the emission of fluorescein in labeled complements and compared to the commercially available dabcyl and Black Hole Quencher 2 (BHQ2), which were conjugated as phosphoramidites. Results show that the new quenchers possess slightly different absorbance properties compared to dabcyl and are as efficient as the commercial quenchers in quenching fluorescein emission. Hydrazone-based quenchers were further successfully incorporated into molecular beacons and shown to give high signal to background ratios in single nucleotide polymorphism detection in vitro. Finally, aminooxy and hydrazine quenchers were applied to quenching of an aldehyde-containing fluorophore associated with living cells, demonstrating cellular quenching within one hour.