Sialyl glycosides anomeric effect

Seldomycin factor 2, 131 Selectins, 358, 366, 420 Shikimate pathway, 471 (-)-Shikimic acid, 572 Showdomycin, 530 Sialyi dimeric Le 324 Sialyl glycosides, 357 p-acetonitrilium ion, 362 anomeric effect, 362 benzeneselenyl triflate, 359 biology, 366, 419, 421, 436, 445... 

In 1991, the syntheses of sialyl C-glycosides were introduced by Bednarski et ah, Paulsen et ah, and Vasella et al. Bednarski and Paulsen exploited a 2-halogeno derivative of Neu5Ac as a precursor of the anomeric radical, which was anticipated to be stabilized by the capto-dative effect of the C1 carboxylate group and ring oxygen. Bednarski reacted the 2-chloro derivative 195 with allyltributyltin and a catalytic amount of bis(tributyltin), and photolized for 18 h to obtain C-glycoside 196 as a 1/1 of anomeric mixture in 65% yield (O Scheme 53) [129]. 

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