Synthesis of Conformationally Locked Carbocyclic Nucleosides Built on a Thiabicyclo[3.1.0]hexane System as a Pseudosugar Surrogate

Abstract

AbstractThe synthesis of prototype models of purine and pyrimidine carbanucleosides built on a 6‐thiabicyclo[3.1.0]hexane system as pseudosugar moiety has been investigated. These pyrimidine carbanucleosides proved to be very stable compounds, in contrast to the parent epoxy analogs, which experienced epoxide ring‐opening due to intramolecular enol base attack. In addition, as the synthesis of a thiirane moiety fused to a five‐membered ring is not a trivial synthetic task, validation and optimization of the existing methods for episulfide preparation were required to access the committed synthetic precursor of the title compounds: (±)‐(1RS,2RS,5SR)‐6‐thiabicyclo[3.1.0]hexan‐2‐ol, compound 28. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)