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Abstract A new family of hydrazone modified cytidine phosphoramidite building block was synthesized and incorporated into oligodeoxynucleotides to construct photoswitchable DNA strands. TheE‐Zisomerization triggered by the irradiation of blue light with a wavelength of 450 nm was investigated and confirmed by1H NMR spectroscopy and HPLC in the contexts of both nucleoside and oligodeoxynucleotide. The light activatedZform isomer of this hydrazone‐cytidine with a six‐member intramolecular hydrogen bond was found to inhibit DNA synthesis in the primer extension model by usingBstDNA polymerase. In addition, the hydrazone modification caused the misincorporation of dATP together with dGTP into the growing DNA strand with similar selectivity, highlighting a potential G to A mutation. This work provides a novel functional DNA building block and an additional molecular tool that has potential chemical biology and biomedicinal applications to control DNA synthesis and DNA‐enzyme interactions using the cell friendly blue light irradiation.
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ortho ‐Boronic Acid Carbonyl Compounds and Their Applications in Chemical Biology**
Abstract Iminoboronates and diazaborines are related classes of compounds that feature an imineorthoto an arylboronic acid (iminoboronate) or a hydrazone that cyclizes with anorthoarylboronic acid (diazaborine). Rather than acting as independent chemical motifs, the arylboronic acid impacts the rate of imine/hydrazone formation, hydrolysis, and exchange with competing nucleophiles. Increasing evidence has shown that the imine/hydrazone functionality also impacts arylboronic acid reactivity toward diols and reactive oxygen and nitrogen species (ROS/RNS). Untangling the communication between C=N linked functionalities and arylboronic acids has revealed a powerful and tunable motif for bioconjugation chemistries and other applications in chemical biology. Here, we survey the applications of iminoboronates and diazaborines in these fields with an eye toward understanding their utility as a function of neighboring group effects.
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- Award ID(s):
- 2238563
- PAR ID:
- 10480005
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 30
- Issue:
- 7
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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