Abstract
A set of unique nucleoside analogs, containing ‘spirocyclic orthoester-type’ scaffolds, were synthesized from a common isothiazolo[4,3-d]pyrimidine-riboside precursor. The key reaction, using 1,2-di-heteroatomic nucleophiles (e.g., 1,2-ethandithiol) and BF3•OEt2, converts an exocyclic imine into the spirocyclic analogs. The novel structural scaffold is confirmed through the use of one- and two-dimensional 1H and 13C NMR experiments.
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Acknowledgements
We thank the National Institutes of Health for generous support (via grant number GM 069773), the Chemistry and Biochemistry MS Facility and the UCSD NMR Facility.
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Dedicated to Professor KC Nicolaou for his contributions to synthetic organic chemistry.
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Rovira, A., Tor, Y. Synthesis of unique spirocyclic orthoester-type derivatives of isothiazolo[4,3-d]pyrimidine nucleosides. J Antibiot 71, 342–344 (2018). https://doi.org/10.1038/ja.2017.87
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DOI: https://doi.org/10.1038/ja.2017.87
