Phosphorus Iodide Links

So-called C-linked calixsugars were prepared by Wittig reaction of the calix[4]arene tetraaldehyde 33 with galactose-6- or ribose-5-phosphorus ylids (obtained in situ from the known phosphonium iodides, Figure 5)70 followed by reduction of the double bonds and deprotection of the hydroxyl groups. Thus, the tetra- and trigalactosides 34c,d (all as P-anomers) and tetra- and tri-L-lyxosides 34 (as a mixture of a- and P-anomers) were obtained. 

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