Eur. J. Org. Chem., 2003: 2911–2918. doi: 10.1002/ejoc.200300177
Mycobacterium tuberculosis thymidine monophosphate kinase (TMPKmt) has recently been introduced as a potential target for the structure-based design of anti-tuberculosis drugs. Based on the TMPKmt X-ray structure and previous S.A.R. studies, we synthesised the nucleoside analogues 3a−b, 6a−b, 7a−b, and 8a−b, modified in 2′- and 3′-position of the ribofuranose ring moiety. To our surprise, these analogues showed only moderate binding affinity (i.e. Ki between 118 and 1260 μM). This prompted us to investigate the conformational features of these nucleosides. We concluded that compounds of this series, especially 8a−b, are strongly biased towards the “Northern” furanose ring conformation, whereas X-ray crystallography reveals a preference of TMPKmt for the opposite “Southern” conformers. This paper covers the synthesis, biological evaluation and conformational features (i.e. preferred ring puckering) of the 2′- and 3′-modified dT analogues.