Phytoalexin-elicitor active oligosaccharide

SCHEME 27. Steric hindrance-facilitated synthesis157 of phytoalexin-elicitor active oligosaccharide 149. 

R. Geurtsen, F. Cote, M. G. Hahn, and G.-J. Boons, Chemoselective glycosylation strategy for the convergent assembly of phytoalexin-elicitor active oligosaccharides and their photoreactive derivatives, /. Org. Chem., 64 (1999) 7828-7835. 

As an exact analog of the phytoalexin elicitor branched heptasaccharide 82 the branched SPH 83 was devised with four amide bonds replacing the 1 -> 6 linkages of the pentasaccharide backbone and thus producing the same length. No elicitor activity was detected for 83, possibly because of the reduced flexibility or different conformation of the mimetic structure [56]. Mimetics of the sialyl Lewis and sialyl Lewis oligosaccharides have recently foimd increased attention. Baisch and... 

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