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Abstract This article contains detailed synthetic protocols for preparation of 5‐cyanomethyluridine (cnm5U) and 5‐cyanouridine (cn5U) phosphoramidites. The synthesis of the cnm5U phosphoramidite building block starts with commercially available 5‐methyluridine (m5C), followed by bromination of the 5‐methyl group to install the cyano moiety using TMSCN/TBAF. The cn5U phosphoramidite is obtained by regular Vorbrüggen glycosylation of the protected ribofuranose with silylated 5‐cyanouracil. These two modified phosphoramidites are suitable for synthesis of RNA oligonucleotides on solid phase using conventional amidite chemistry. Our protocol provides access to two novel building blocks for constructing RNA‐based therapeutics. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Preparation of cnm5U and cn5U phosphoramidites Basic Protocol 2: Synthesis, purification, and characterization of cnm5U‐ and cn5U‐modified RNA oligonucleotides
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Low‐scale syringe‐made synthesis of 15 N‐labeled oligonucleotides
Fast and reasonable low‐scale (200 nmol) syringe‐made synthesis of15N‐labeled oligonucleotides representing DNA trinucleotide codons is communicated. All codons were prepared by solid‐phase controlled pore glass synthesis column technique via the phosphoramidite method. Twenty‐four labeled oligonucleotides covering the DNA genetic code alphabet were prepared using commercially available reagents and affordable equipment in a reasonably short period of time, with acceptable yields and purity for direct applications in mass spectrometry.
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- Award ID(s):
- 1951518
- PAR ID:
- 10375858
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Labelled Compounds and Radiopharmaceuticals
- Volume:
- 65
- Issue:
- 12
- ISSN:
- 0362-4803
- Page Range / eLocation ID:
- p. 309-314
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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