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Updated: Jul 3, 2025

Targeted DNA Methylation Analysis by Next-generation Sequencing
Published on: February 24, 2015
Selective Methylation of Nucleosides via an In Situ Generated Methyl Oxonium
Xiao-Yang Jin1, Yin-Ming He1,2, Tian-He Hui1,3,2
1Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Abstract:
A very mild and efficient procedure has been developed for the preparation of N-methylated uridine, pseudouridine, guanosine and inosine derivatives. This process was compatible with free hydroxyls within the ribose and did not require precautions on the protection or deprotection of other functionalities. The key to this extremely mild methylation without protection relied on the in situ generated methyl oxonium from the Wittig reagent and methanol. A putative mechanism for the selective methylation was also proposed.
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