Synthetic studies directed toward the assembly of the C-glycoside fragment of the telomerase inhibitor D8646-2-6.

  title={Synthetic studies directed toward the assembly of the C-glycoside fragment of the telomerase inhibitor D8646-2-6.},
  author={Akira Kanai and Tomoyuki Kamino and Kouji Kuramochi and Susumu Kobayashi},
  journal={Organic letters},
  volume={5 16},
[reaction: see text] Construction and characterization of the C-glycosidic moiety of telomerase inhibitor D8646-2-6 (1) are described. This is the first example of the C-glycosylation using electron-poor aromatics, 4-hydroxypyrone, as a glycosyl acceptor. The glycosylation reaction and base-promoted isomerization affords desired beta-C-glycoside in a 61% overall yield. 
Synthetic study on telomerase inhibitor, D8646-2-6: synthesis of the key intermediate using Sn(OTf)2 or Sc(OTf)3 mediated aldol-type reaction and Stille coupling.
The synthesis of the key intermediate (4) in the proposed route to D8646-2-6 is described and the stepwise dehydration reaction of the aldol adduct 14, followed by Stille coupling with vinyl stannane 5 which contained phosphonate gave the desired 4.
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