The potentially versatile N-unprotected 8-formyl derivatives of adenosine and 2’-deoxyadenosine are highly underexploited for C8 modifications of these nucleosides. Only in situ formation of 8-formyladenosine is known and a single application of an N-benzoyl derivative has been reported. On the other hand, 8-formyl-2’-deoxyadenosine and its applications remain unknown. Herein, we report straightforward, scalable syntheses of both N-unprotected 8-formyladenine nucleoside derivatives, and demonstrate broad diversification at the C8 position by hydroxymethylation, azidation, CuAAC ligation, reductive amination, as well as olefination and fluoroolefination with modified Julia and a Horner-Wadsworth-Emmons reagents.
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A photochemical C=C cleavage process: toward access to backbone N -formyl peptides
Photo-responsive modifications and photo-uncaging concepts are useful for spatiotemporal control of peptides structure and function. While side chain photo-responsive modifications are relatively common, access to photo-responsive modifications of backbone N–H bonds is quite limited. This letter describes a new photocleavage pathway, affording N -formyl amides from vinylogous nitroaryl precursors under physiologically relevant conditions via a formal oxidative C=C cleavage. The N -formyl amide products have unique properties and reactivity, but are difficult or impossible to access by traditional synthetic approaches.
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- Award ID(s):
- 1904865
- PAR ID:
- 10390884
- Date Published:
- Journal Name:
- Beilstein Journal of Organic Chemistry
- Volume:
- 17
- ISSN:
- 1860-5397
- Page Range / eLocation ID:
- 2932 to 2938
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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