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4-Nitrophenyl activated esters are superior synthons for indirect radiofluorination of biomolecules.

ABSTRACT: Indirect radiolabelling has for a long time been the mainstay strategy for radiofluorination of biomolecules. Acylation of biomolecules through the use of an ¹⁸F-labelled activated ester is a standard method for indirect radiolabelling. However, the preparation of ¹⁸F-labelled activated esters is typically a complex and multistep procedure. Herein, we describe the use of 4-nitrophenyl (PNP) activated esters to rapidly prepare ¹⁸F-labelled acylation synthons in one step. Furthermore, we present a comparative study of PNP activated esters and the commonly utilised 2,3,5,6-tetrafluorphenyl (TFP) activated esters under direct radiofluorination conditions and demonstrate their relative acylation behaviour. We demonstrate the superiority of PNP esters under direct radiofluorination conditions with favourable acylation kinetics.

SUBMITTER: Haskali MB

PROVIDER: S-EPMC7517343 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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4-Nitrophenyl activated esters are superior synthons for indirect radiofluorination of biomolecules.

Haskali Mohammad B MB Farnsworth Ashleigh L AL Roselt Peter D PD Hutton Craig A CA

RSC medicinal chemistry 20200707 8

Indirect radiolabelling has for a long time been the mainstay strategy for radiofluorination of biomolecules. Acylation of biomolecules through the use of an 18F-labelled activated ester is a standard method for indirect radiolabelling. However, the preparation of 18F-labelled activated esters is typically a complex and multistep procedure. Herein, we describe the use of 4-nitrophenyl (PNP) activated esters to rapidly prepare 18F-labelled acylation synthons in on ...[more]

PMID: 33479687

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