unsaturated iminosugars has not yet been extensively studied because of a lack of general synthetic methods. A practical synthesis of these cyclic ketimine sugars was developed, which was based on a tandem addition−cyclization reaction of a Grignard reagent to a ω-methanesulfonylglycononitrile.
Polyhydroxy 4-azaspiro[2.4]heptane derivatives (spirocyclopropyl iminosugars) were prepared in four to six steps from readily available protected aldoses. The key step of the reaction sequence involves a titanium-mediated aminocyclopropanation of glycononitriles with subsequent cyclization. Five new polyhydroxypyrrolidines so-obtained have been evaluated for their ability to inhibit 16 glycosidases. One of them exhibits selective inhibition Of alpha-L-fucosidase from bovine kidney (K-i = 1.6 mu M, competitive). (c) 2006 Elsevier Ltd. All rights reserved.
BUCHANAN, J. GRANT;LUMBARD, KEITH W.;STURGEON, ROBERT J.;THOMPSON, DERYK +, J. CHEM. SOC. PERKIN TRANS. PT 1,(1990) N, C. 699-706
作者:BUCHANAN, J. GRANT、LUMBARD, KEITH W.、STURGEON, ROBERT J.、THOMPSON, DERYK +