Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2021 Apr 16;89:132159. doi: 10.1016/j.tet.2021.132159

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© 2021 Elsevier Ltd. All rights reserved.

Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active.

PMC Copyright notice

Scheme 1 — Synthesis of 2′-fluorotetradialdose nucleoside phosphonates. Reagents and conditions: (a) HCl, MeOH, rt, 16 h, quant.; (b) p-Toluoyl chloride, pyridine, 0 °C to rt, 16 h, 48%; (c) DAST, MeCN, 0 °C to rt, 16 h, 54%; (d) H₂SO₄, Ac₂O, AcOH, 0 °C to rt, 2 h, 84%; (e) hexamethyldisilazane, (iPrO)₂P(O)CH₂OH, saccharine, 100 °C, 8 h; (f) SnCl₄, MeCN, 55 °C, 1 h; (g) MeNH₂, EtOH, rt, 16 h, 85%; (h) DMTrCl, pyridine, rt, 16 h; (i) BzCl, DMAP, pyridine, rt, 8 h; (j) TFA, DCM, rt, 10 min, 74%; (k) PhI(OAc)₂, TEMPO, MeCN, rt, 16 h, 90%; (l) Pb(OAc)₄, THF, rt, 16 h, 60%; (m) SnCl₄, DCE, BSA, N6-benzoyladenine, rt, 30 min 43%; (n) TMSBr, pyridine, rt, 8 h; (o) MeNH₂, EtOH, rt, 73%.